Relay 46 Definitive Test
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Relay 46 Definitive Test
I've been trying to think of a way to prove/disprove relay 46's involvement in the dreaded DBS. This is what I've came up with:
Install a low amp fuse (preferably 1 amp) into Fuse 18 HDLP WASH in the main fuseblock under the hood and reinstall relay 46. If the relay's presence is the cause, the fuse you installed will blow, you will not get a dead battery since the fuse with blow and stop the current drain. A blown fuse would prove current passed through that relay.
The details of how I came up with this are below for those interested....
Battery has about 110 Amp Hour of reserve, therefore, to kill the battery in 24 hours would take 4.6 amps and for 12 hours it would take a 9.2 amp draw. I think that we can all agree that it is at least a 1 amp draw,though that should take 110 hours or 4.6 days, but is certainly an unacceptable draw.
Looking at relay 46, it has four tabs. They are setup so that 2 tabs are connected (high current) when voltage is applied at the other 2 tabs (low current, control). Each tab that makes up a pair is diagonal from the other, that is why it doesn't matter which way you insert it.
According to service manual, one is connected to the 20 amp fuse 18. This is the main power that is switched by the relay. The tab diagonally from it is connected to the headlamp washer pump. For the other two tabs that make up the low current control, one connects to the body computer and the other is grounded.
If you look at all the possible differences that could occur with the relay in place and not in place, the only logical place for the draw is through fuse 18, which is why placing a low amp fuse there will detect if this is the issue. The low current coil side could not cause DBS if the relay is not damaged because the current draw is too low to drain the battery in a couple days. You could test this by conned the coil directly to your battery, this would cause DBS in about 14 days. If the relay was damaged, the issue would be corrected with a new relay and in a lot of cases the detected method would still have found it.
Final note to advanced types:
You could also disassembly the relay and install small fuses inline with each circuit to detect for other current paths.
Install a low amp fuse (preferably 1 amp) into Fuse 18 HDLP WASH in the main fuseblock under the hood and reinstall relay 46. If the relay's presence is the cause, the fuse you installed will blow, you will not get a dead battery since the fuse with blow and stop the current drain. A blown fuse would prove current passed through that relay.
The details of how I came up with this are below for those interested....
Battery has about 110 Amp Hour of reserve, therefore, to kill the battery in 24 hours would take 4.6 amps and for 12 hours it would take a 9.2 amp draw. I think that we can all agree that it is at least a 1 amp draw,though that should take 110 hours or 4.6 days, but is certainly an unacceptable draw.
Looking at relay 46, it has four tabs. They are setup so that 2 tabs are connected (high current) when voltage is applied at the other 2 tabs (low current, control). Each tab that makes up a pair is diagonal from the other, that is why it doesn't matter which way you insert it.
According to service manual, one is connected to the 20 amp fuse 18. This is the main power that is switched by the relay. The tab diagonally from it is connected to the headlamp washer pump. For the other two tabs that make up the low current control, one connects to the body computer and the other is grounded.
If you look at all the possible differences that could occur with the relay in place and not in place, the only logical place for the draw is through fuse 18, which is why placing a low amp fuse there will detect if this is the issue. The low current coil side could not cause DBS if the relay is not damaged because the current draw is too low to drain the battery in a couple days. You could test this by conned the coil directly to your battery, this would cause DBS in about 14 days. If the relay was damaged, the issue would be corrected with a new relay and in a lot of cases the detected method would still have found it.
Final note to advanced types:
You could also disassembly the relay and install small fuses inline with each circuit to detect for other current paths.
Last edited by OttoNP; Jun 29, 2005 at 11:08 AM.
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This would only tell you that you have a draw, it would tell you nothing about the location of it. To see if relay 46 is the cause, you need to isolate that circuit, which the above test does. My personal opinion is that it is not relay 46.
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From: Arizona
Originally Posted by MitchAlsup
Or:
You could put an amp meter between the battery and the battery cable and simply measure the current draw with the key out of the system.
You could put an amp meter between the battery and the battery cable and simply measure the current draw with the key out of the system.
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You'd still have the same problem of not knowing the cause of the draw. That is the beauty of putting a low rate fuse in position 18. Once it blows, which it will if you get a draw through that line, you will know for sure. You could run the test for 6 months....
I could try it with my car, but I've never had a dead battery without knowing the cause (driver error). I still have relay 46 in. So what we need is someone that has had DBS and pulled relay 46 and now does not have DBS. This will tell us if it was a coincidence or the real cause.
I could try it with my car, but I've never had a dead battery without knowing the cause (driver error). I still have relay 46 in. So what we need is someone that has had DBS and pulled relay 46 and now does not have DBS. This will tell us if it was a coincidence or the real cause.
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From: Arizona
Originally Posted by OttoNP
You'd still have the same problem of not knowing the cause of the draw. That is the beauty of putting a low rate fuse in position 18. Once it blows, which it will if you get a draw through that line, you will know for sure. You could run the test for 6 months....
I could try it with my car, but I've never had a dead battery without knowing the cause (driver error). I still have relay 46 in. So what we need is someone that has had DBS and pulled relay 46 and now does not have DBS. This will tell us if it was a coincidence or the real cause.
I could try it with my car, but I've never had a dead battery without knowing the cause (driver error). I still have relay 46 in. So what we need is someone that has had DBS and pulled relay 46 and now does not have DBS. This will tell us if it was a coincidence or the real cause.
And what, I'll have to check the fuse every so often to see if it's blown?
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Originally Posted by OttoNP
I've been trying to think of a way to prove/disprove relay 46's involvement in the dreaded DBS. This is what I've came up with:
Install a low amp fuse (preferably 1 amp) into Fuse 18 HDLP WASH in the main fuseblock under the hood and reinstall relay 46. If the relay's presence is the cause, the fuse you installed will blow, you will not get a dead battery since the fuse with blow and stop the current drain. A blown fuse would prove current passed through that relay.
The details of how I came up with this are below for those interested....
Battery has about 110 Amp Hour of reserve, therefore, to kill the battery in 24 hours would take 4.6 amps and for 12 hours it would take a 9.2 amp draw. I think that we can all agree that it is at least a 1 amp draw,though that should take 110 hours or 4.6 days, but is certainly an unacceptable draw.
Looking at relay 46, it has four tabs. They are setup so that 2 tabs are connected (high current) when voltage is applied at the other 2 tabs (low current, control). Each tab that makes up a pair is diagonal from the other, that is why it doesn't matter which way you insert it.
According to service manual, one is connected to the 20 amp fuse 18. This is the main power that is switched by the relay. The tab diagonally from it is connected to the headlamp washer pump. For the other two tabs that make up the low current control, one connects to the body computer and the other is grounded.
If you look at all the possible differences that could occur with the relay in place and not in place, the only logical place for the draw is through fuse 18, which is why placing a low amp fuse there will detect if this is the issue. The low current coil side could not cause DBS if the relay is not damaged because the current draw is too low to drain the battery in a couple days. You could test this by conned the coil directly to your battery, this would cause DBS in about 14 days. If the relay was damaged, the issue would be corrected with a new relay and in a lot of cases the detected method would still have found it.
Final note to advanced types:
You could also disassembly the relay and install small fuses inline with each circuit to detect for other current paths.
Install a low amp fuse (preferably 1 amp) into Fuse 18 HDLP WASH in the main fuseblock under the hood and reinstall relay 46. If the relay's presence is the cause, the fuse you installed will blow, you will not get a dead battery since the fuse with blow and stop the current drain. A blown fuse would prove current passed through that relay.
The details of how I came up with this are below for those interested....
Battery has about 110 Amp Hour of reserve, therefore, to kill the battery in 24 hours would take 4.6 amps and for 12 hours it would take a 9.2 amp draw. I think that we can all agree that it is at least a 1 amp draw,though that should take 110 hours or 4.6 days, but is certainly an unacceptable draw.
Looking at relay 46, it has four tabs. They are setup so that 2 tabs are connected (high current) when voltage is applied at the other 2 tabs (low current, control). Each tab that makes up a pair is diagonal from the other, that is why it doesn't matter which way you insert it.
According to service manual, one is connected to the 20 amp fuse 18. This is the main power that is switched by the relay. The tab diagonally from it is connected to the headlamp washer pump. For the other two tabs that make up the low current control, one connects to the body computer and the other is grounded.
If you look at all the possible differences that could occur with the relay in place and not in place, the only logical place for the draw is through fuse 18, which is why placing a low amp fuse there will detect if this is the issue. The low current coil side could not cause DBS if the relay is not damaged because the current draw is too low to drain the battery in a couple days. You could test this by conned the coil directly to your battery, this would cause DBS in about 14 days. If the relay was damaged, the issue would be corrected with a new relay and in a lot of cases the detected method would still have found it.
Final note to advanced types:
You could also disassembly the relay and install small fuses inline with each circuit to detect for other current paths.
It is more likely that what is happening is that the BCM is activating the relay because of a software bug, but the leads to the non-existent headlight washer motors are *not* shorted. Now the coil of that relay draws about 100 mA. The terminal voltage of a lead acid starting battery will drop from 12.5 volts to 10.5 volts after 10% of its rated capacity is drawn. That's the maximum amount you can draw from a starting battery without damaging it. The car won't start with a battery voltage of 10.5 or lower. If the battery has 110 Ah capacity, and I think that's wrong, a type 74 battery is typically 65 Ah, 10% of that capacity is 11 or 6.5 Ah respectively. So a 100 mA discharge will discharge the battery in 110 or 65 hours respectively. I think the latter figure is correct, so you'd have DBS in less than 3 days with only the 100 mA draw of the relay coil. A *very* simple test for this is to touch the relay coil and see if it is warm. 100 mA at 12 volts is 1.2 watts, and that'll make the coil warm to the touch.
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From: Arizona
Originally Posted by shopdog
I don't believe your proposal will net any useful results. There would have to be a *partial* short in the wiring to the nonexistent headlight washer motors. If there were an ordinary short, the original 20A fuse would blow. A *partial* short that would blow a 1A fuse and not a 20A fuse is very difficult to imagine. It would have to be less than 12 ohms but more than 1.2 ohms. Typically, you'd have a hard short, which would blow the 20A fuse, or you wouldn't have a short at all.
It is more likely that what is happening is that the BCM is activating the relay because of a software bug, but the leads to the non-existent headlight washer motors are *not* shorted. Now the coil of that relay draws about 100 mA. The terminal voltage of a lead acid starting battery will drop from 12.5 volts to 10.5 volts after 10% of its rated capacity is drawn. That's the maximum amount you can draw from a starting battery without damaging it. The car won't start with a battery voltage of 10.5 or lower. If the battery has 110 Ah capacity, and I think that's wrong, a type 74 battery is typically 65 Ah, 10% of that capacity is 11 or 6.5 Ah respectively. So a 100 mA discharge will discharge the battery in 110 or 65 hours respectively. I think the latter figure is correct, so you'd have DBS in less than 3 days with only the 100 mA draw of the relay coil. A *very* simple test for this is to touch the relay coil and see if it is warm. 100 mA at 12 volts is 1.2 watts, and that'll make the coil warm to the touch.
It is more likely that what is happening is that the BCM is activating the relay because of a software bug, but the leads to the non-existent headlight washer motors are *not* shorted. Now the coil of that relay draws about 100 mA. The terminal voltage of a lead acid starting battery will drop from 12.5 volts to 10.5 volts after 10% of its rated capacity is drawn. That's the maximum amount you can draw from a starting battery without damaging it. The car won't start with a battery voltage of 10.5 or lower. If the battery has 110 Ah capacity, and I think that's wrong, a type 74 battery is typically 65 Ah, 10% of that capacity is 11 or 6.5 Ah respectively. So a 100 mA discharge will discharge the battery in 110 or 65 hours respectively. I think the latter figure is correct, so you'd have DBS in less than 3 days with only the 100 mA draw of the relay coil. A *very* simple test for this is to touch the relay coil and see if it is warm. 100 mA at 12 volts is 1.2 watts, and that'll make the coil warm to the touch.
I also think, however, that we're looking at a software bug, and not a hardware gremlin.
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Melting Slicks
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From: Southwest Florida
Originally Posted by shopdog
I don't believe your proposal will net any useful results. There would have to be a *partial* short in the wiring to the nonexistent headlight washer motors. If there were an ordinary short, the original 20A fuse would blow. A *partial* short that would blow a 1A fuse and not a 20A fuse is very difficult to imagine. It would have to be less than 12 ohms but more than 1.2 ohms. Typically, you'd have a hard short, which would blow the 20A fuse, or you wouldn't have a short at all.
It is more likely that what is happening is that the BCM is activating the relay because of a software bug, but the leads to the non-existent headlight washer motors are *not* shorted. Now the coil of that relay draws about 100 mA. The terminal voltage of a lead acid starting battery will drop from 12.5 volts to 10.5 volts after 10% of its rated capacity is drawn. That's the maximum amount you can draw from a starting battery without damaging it. The car won't start with a battery voltage of 10.5 or lower. If the battery has 110 Ah capacity, and I think that's wrong, a type 74 battery is typically 65 Ah, 10% of that capacity is 11 or 6.5 Ah respectively. So a 100 mA discharge will discharge the battery in 110 or 65 hours respectively. I think the latter figure is correct, so you'd have DBS in less than 3 days with only the 100 mA draw of the relay coil. A *very* simple test for this is to touch the relay coil and see if it is warm. 100 mA at 12 volts is 1.2 watts, and that'll make the coil warm to the touch.
It is more likely that what is happening is that the BCM is activating the relay because of a software bug, but the leads to the non-existent headlight washer motors are *not* shorted. Now the coil of that relay draws about 100 mA. The terminal voltage of a lead acid starting battery will drop from 12.5 volts to 10.5 volts after 10% of its rated capacity is drawn. That's the maximum amount you can draw from a starting battery without damaging it. The car won't start with a battery voltage of 10.5 or lower. If the battery has 110 Ah capacity, and I think that's wrong, a type 74 battery is typically 65 Ah, 10% of that capacity is 11 or 6.5 Ah respectively. So a 100 mA discharge will discharge the battery in 110 or 65 hours respectively. I think the latter figure is correct, so you'd have DBS in less than 3 days with only the 100 mA draw of the relay coil. A *very* simple test for this is to touch the relay coil and see if it is warm. 100 mA at 12 volts is 1.2 watts, and that'll make the coil warm to the touch.
Not that the original idea isn't worth merit, but ShopDog's post I believe is more accurate with respect to how long and how much it will take to drain the battery. It doesn't take that much. Also, in a thread a digitalcorvettes, one person actually tracked down the current drain to relay 46 and said that the drain was 148 mA (from memory but I think I'm close) with the relay in. Pulled the relay and it dropped to 2-3 mA. I think this is a software bug that actuates the relay and the current draw of the relay's coil is what is causing the draw. If this is the case, replacing a fuse in the circuit controlled by relay 46 probably won't affect anything since the draw isn't in the circuit itself but rather the relay. All supposition of course but it all fits with what the one and only person found when diagnosing the relay 46 circuit.
Mike
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I totally agree with just about everything you guys are saying except for a couple things.
I agree that a draw between 1 amp and 20 amp would be weird(I'd expect short or open as well), but I have no ideal where those wires go when the option isn't present. Maybe the motor is still there (doubt it though? I'd guess the connector is still there, maybe on some vehicles it gets accidentally plugged in to something? I can't imagine the coil current draw being enough to kill the battery overnight. Or maybe the connector is just laying there exposed and it gets caked over?
I do think it will take longer for a relay coil to cause DBS, even with your estimate with 10% of 65 AH it would take 3 days and some people are reporting dead batteries overnight. Another test alternate to the warm relay is to remove/install relay and listen for a click.
Also, I believed that amp hours was the number of amp hours to drop the battery to 10.5V,not 10% of it. Just as reserve capacity is the number of minutes a fully charged battery will output 25 amps until reaching 10.5V. I've never done any real life testing of these and you definitely know your stuff....
but from http://www.1st-optima-batteries.com/amp_hours.asp
"The Amp Hour rating tells you how much amperage is available when discharged evenly over a 20 hour period. The amp hour rating is cumulative, so in order to know how many constant amps the battery will output for 20 hours, you have to divide the amp hour rating by 20. Example: If a battery has an amp hour rating of 75, dividing by 20 = 3.75. Such a battery can carry a 3.75 amp load for 20 hours before dropping to 10.5 volts. (10.5 volts is the fully discharged level, at which point the battery needs to be recharged.) A battery with an amp hour rating of 55 will carry a 2.75 amp load for 20 hours before dropping to 10.5 volts."
Also, if it was 65 amp hours and it would only take a loss of 6.5 amp hours to make the car unstartable, I would think you'd tear through that pretty quickly just listening to your radio, maybe less depending on your volume.
I'm going to try testing that relay on a battery I have laying around...I'll try to get a chart out of it.
As far as a software bug, it could be something like that, but just as I would think there would be an open or short on the line, I find it hard to believe that the BCM would cut power to everyting except for a particular relay. I would think that whatever feeds the power for that relay is cut when the main power for the BCM is turned off. In other words, I'd expect that either the whole BCM to be powered up or none of it, not just one relay control. I totally think this may be cause from the whole BCM not shutting down - this is close to what happens when you don't shift to reverse, though other stuff is up and running too.
Another difficulty facing us is Onstar. It will periodically power up to do some stuff and shut down for around the first 48 hours or so. If you were checking batteries draws with a multimeter, this could confuse you.
I don't know why I'm doing all this work for something that has never happened to my car...
I agree that a draw between 1 amp and 20 amp would be weird(I'd expect short or open as well), but I have no ideal where those wires go when the option isn't present. Maybe the motor is still there (doubt it though? I'd guess the connector is still there, maybe on some vehicles it gets accidentally plugged in to something? I can't imagine the coil current draw being enough to kill the battery overnight. Or maybe the connector is just laying there exposed and it gets caked over?
I do think it will take longer for a relay coil to cause DBS, even with your estimate with 10% of 65 AH it would take 3 days and some people are reporting dead batteries overnight. Another test alternate to the warm relay is to remove/install relay and listen for a click.
Also, I believed that amp hours was the number of amp hours to drop the battery to 10.5V,not 10% of it. Just as reserve capacity is the number of minutes a fully charged battery will output 25 amps until reaching 10.5V. I've never done any real life testing of these and you definitely know your stuff....
but from http://www.1st-optima-batteries.com/amp_hours.asp
"The Amp Hour rating tells you how much amperage is available when discharged evenly over a 20 hour period. The amp hour rating is cumulative, so in order to know how many constant amps the battery will output for 20 hours, you have to divide the amp hour rating by 20. Example: If a battery has an amp hour rating of 75, dividing by 20 = 3.75. Such a battery can carry a 3.75 amp load for 20 hours before dropping to 10.5 volts. (10.5 volts is the fully discharged level, at which point the battery needs to be recharged.) A battery with an amp hour rating of 55 will carry a 2.75 amp load for 20 hours before dropping to 10.5 volts."
Also, if it was 65 amp hours and it would only take a loss of 6.5 amp hours to make the car unstartable, I would think you'd tear through that pretty quickly just listening to your radio, maybe less depending on your volume.
I'm going to try testing that relay on a battery I have laying around...I'll try to get a chart out of it.
As far as a software bug, it could be something like that, but just as I would think there would be an open or short on the line, I find it hard to believe that the BCM would cut power to everyting except for a particular relay. I would think that whatever feeds the power for that relay is cut when the main power for the BCM is turned off. In other words, I'd expect that either the whole BCM to be powered up or none of it, not just one relay control. I totally think this may be cause from the whole BCM not shutting down - this is close to what happens when you don't shift to reverse, though other stuff is up and running too.
Another difficulty facing us is Onstar. It will periodically power up to do some stuff and shut down for around the first 48 hours or so. If you were checking batteries draws with a multimeter, this could confuse you.
I don't know why I'm doing all this work for something that has never happened to my car...
Last edited by OttoNP; Jun 30, 2005 at 08:25 AM.
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Sorry if I missed it, but does anyone know how the headlight washers are activated on the european models? Is there a separate switch, or are they somehow activated by the "stalk" that controls the windshield wipers.
I don't know if this would be pertinent or not, but it seems like knowing this could (possibly) help figure out what causes the problem.
BTW, some excellent technical posts on this thread - thanks!
I don't know if this would be pertinent or not, but it seems like knowing this could (possibly) help figure out what causes the problem.
BTW, some excellent technical posts on this thread - thanks!
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Looking at the schematics it looks like they turn on when you use your windshield washer because I can't find a separate button anywhere, though the control is a separate relay and separate pin on the BCM.
I know that on the SRX with headlamps washer it is controlled in this way.
I know that on the SRX with headlamps washer it is controlled in this way.
Melting Slicks
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From: Southwest Florida
Originally Posted by OttoNP
I don't know why I'm doing all this work for something that has never happened to my car...
Seems like GM is not interested and being an intermittent problem, it is hard to find or test. When DBS happened to me the one time it happened, my battery was down to 2.42 volts!
I felt the relay and listened for a click at that point but it obviously didn't have enough juice left to actuate the relay by the time it got to 2.42 volts.There are a lot of complications in doing your research, one being that it is an intermittent problem so is hard to test, and another being that there may be multiple causes for the problem. In my case, for example, there was nothing wrong with the battery itself. In a few cases, however, the battery was the cause. In yet other cases, not putting the car in reverse was the cause. This all complicates the issue. Add to that the fact that some of us let our cars sit a few days at a time, and it means we really don't know the amount of time necessary to drain the battery when the "real" DBS hits.
As for the software bug idea, software bugs can do literally anything, so most likely no amount of "logic" could make a software bug less or more likely. Like anything else, it is just one of many possible guesses.
Having experienced the problem, I don't think it is an issue with the shutdown sequence itself. When it happened to me, I was in reverse (I always am since I back into the garage) and I didn't get the telltale horn honks or "shift to reverse" DIC message. In addition, I heard the column lock engage and the lights went out as usual, none of which happens if you are not in reverse. I also confirmed that the car was fully in reverse after I found the battery dead. This tells me that it isn't in the shutdown sequence and the car isn't remaining in accessory power. Something else is going on.
When it happened to me, I did notice when shutting the car off the last time before my DBS, the column lock sounded a bit different. I can't explain it but the little "zip" that it makes just didn't sound the same. I noticed when I got back in the car after the DBS that the pin had not engaged in the column. I didn't think anything of it because this is a normal condition: turning the steering wheel just a little bit will allow the pin to poke into place. Since my episode of DBS, out of my own paranoia, I always park with the steering wheel perfectly straight and give it a little jiggle side to side after shutdown to make sure it is locked and the pin is in place. In the back of my mind, I wonder if some condition could cause the column lock solenoid/motor to try to keep pushing the pin in if it isn't fully engaged. Probably a bogus theory, but I thought I'd mention it.
Given the number of people who have reported multiple DBS episodes before pulling relay 46 and then none afterward, I'd have to say relay 46 (or something in that circuit) is the best candidate. I'll go back over to digitalcorvettes and do a search to see if I can find the post where someone actually measured the parasitic draw and whittled it down to the relay 46 circuit. That might give some clues...
Thanks for doing this BTW!
Mike
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Does anyone know if the steering wheel HAS to be locked? I had some episodes of DBS in the past, pre pulling #46, but also didn't realize until more recently that the column even locked! Somehow I thought the reverse thing substituted for the column lock. Anyway, in the past I might not have been locked every time when shut down. Could that drain the battery?
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Originally Posted by mikeyc6
When it happened to me, I did notice when shutting the car off the last time before my DBS, the column lock sounded a bit different. I can't explain it but the little "zip" that it makes just didn't sound the same. I noticed when I got back in the car after the DBS that the pin had not engaged in the column. I didn't think anything of it because this is a normal condition: turning the steering wheel just a little bit will allow the pin to poke into place. Since my episode of DBS, out of my own paranoia, I always park with the steering wheel perfectly straight and give it a little jiggle side to side after shutdown to make sure it is locked and the pin is in place. In the back of my mind, I wonder if some condition could cause the column lock solenoid/motor to try to keep pushing the pin in if it isn't fully engaged. Probably a bogus theory, but I thought I'd mention it.
The car turns off before/during the column lock cycle. Based on your description, I'd say that the battery was low when you turned your vehicle off. The sound of the column lock is fairly proportion to your battery charge, I've killed my battery before while working on my car and that is kind what happend. There is no speed control, the column lock motor gets connected directly to battery. This is very interesting...
As far as the drain goes, I found the post your talking about on this site, it was reported by a dealer to a poster. I don't have much faith in dealerships, that's why I haven't visited one since I was 17.
Intermittant problems like these are the hardest, that's kind of how I thought of that test. I wanted something that would permanently change, show exactly which circuit had the drain, and be easy for almost anyone to do (just switch a fuse). The biggest assumption I had is that the coil alone is not enough to drain the battery, which it may be (I'll test it when I get home)...
Melting Slicks
Joined: Jul 2001
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From: Southwest Florida
Originally Posted by Hoonose
Does anyone know if the steering wheel HAS to be locked? I had some episodes of DBS in the past, pre pulling #46, but also didn't realize until more recently that the column even locked! Somehow I thought the reverse thing substituted for the column lock. Anyway, in the past I might not have been locked every time when shut down. Could that drain the battery?
Mike
Melting Slicks
Joined: Jul 2001
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From: Southwest Florida
Oh, and just to complicate things a bit, I have Lojack. 
I doubt that has anything to do with it because it only happened one time, but I wonder how many people who have DBS have some sort of aftermarket security system? I wouldn't think that would be intermittent though. I can normally leave my car sitting in the middle of winter for a month and it cranks right up. Then 1 time in 100, DBS hits. 
Mike
I doubt that has anything to do with it because it only happened one time, but I wonder how many people who have DBS have some sort of aftermarket security system? I wouldn't think that would be intermittent though. I can normally leave my car sitting in the middle of winter for a month and it cranks right up. Then 1 time in 100, DBS hits. Mike
Thread Starter
Racer
Joined: Nov 2004
Posts: 298
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Also, to clarify a bit, the lock pin is on a spring, so that if it doesn't align with a hole, the spring just compresses. As a result, the alignment doesn't matter. Everything moves to the same position.
Thread Starter
Racer
Joined: Nov 2004
Posts: 298
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Having Lojack will definitely have an effect, especially depending on how they installed it. I would tend to think that the issue would not be as intermittent as you said.
It really sounds like your battery was low when your turned the vehicle off based on the sound of your column lock, what do you think? If you make a lot of short trips or if there is a problem with the charging system, the battery may not get fully charged.
It really sounds like your battery was low when your turned the vehicle off based on the sound of your column lock, what do you think? If you make a lot of short trips or if there is a problem with the charging system, the battery may not get fully charged.
Melting Slicks
Joined: Jul 2001
Posts: 3,284
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From: Southwest Florida
I know you found it already, but for the benefit of others, here is the thread that started the "relay 46 hypothesis". Seems pretty credible, but you never know... I guess it is possible that the dealer couldn't find anything and just wanted an "out".
Since the voltage was all the way down to 2.42 volts when I found it dead, it's probably not that simple. Also, I would think it possible that the battery developed an internal short at some point and it was just the battery... but I was able to hook up a 6 amp charger, charge the battery overnight, and the battery seemed fine.
Mike
Originally Posted by OttoNP
Having Lojack will definitely have an effect, especially depending on how they installed it. I would tend to think that the issue would not be as intermittent as you said.
It really sounds like your battery was low when your turned the vehicle off based on the sound of your column lock, what do you think? If you make a lot of short trips or if there is a problem with the charging system, the battery may not get fully charged.
It really sounds like your battery was low when your turned the vehicle off based on the sound of your column lock, what do you think? If you make a lot of short trips or if there is a problem with the charging system, the battery may not get fully charged.
Mike
Last edited by mikeyc6; Jun 30, 2005 at 11:51 AM.