IMPORTANT ELECTRICAL INFORMATION (Long!)
Thread Starter
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
You have done EVERYTHING correctly so far. The only NEXt STEP is to either replace the door lock relay (its not allowing the correct current to reack the unlock solenoid due to high resistance) or replace the DOOR MODULE.
BC
BC
Ok, I bent all the female pins up on both plugs in both doors. Some were pretty bad. I cleaned the male and female sides. I used liquid tape on the bare comm wire. I also went ahead and cleaned the battery terminals while I had them off.
When I put the door connections back together, they had a LOT more resistance so I believe there is good contact. I also checked my battery had a solid 12 volts while off.
I hook everything back up and cleared the codes. Still no drivers door lock. Just the same as before. I drove a couple places and no codes reappeared.
I can hear a click in the drivers door but only the passenger side works.
What next? Thanks
When I put the door connections back together, they had a LOT more resistance so I believe there is good contact. I also checked my battery had a solid 12 volts while off.
I hook everything back up and cleared the codes. Still no drivers door lock. Just the same as before. I drove a couple places and no codes reappeared.
I can hear a click in the drivers door but only the passenger side works.
What next? Thanks
Cruising
Joined: Jul 2008
Posts: 12
Likes: 0
C5 won't start
Bill,
I have read most of your posts and can’t believe the wealth of knowledge you have. My 2001 C5 won’t start. I have a brand new battery that reads 12+ volts until I hook it up to my car. Then the voltage drops to 5-8 volts. When I turn the ignition switch to the on position the dash attempts to light up but flashes like there is a short somewhere. When I try to start the car I get the standard clicking sound from the starter as if the battery is low. I have tried to jump start the car from another vehicle, to no avail. My car has 30,000 miles on it and has always been stored in a heated, dry garage. It has been driven in the rain only a few times, never in snow.
Following is what I have done as a result of your past posts:
I removed the ignition switch, took it apart and found some burned contacts which I cleaned and put the switch back together.
I have checked all of the ground points that have been discussed numerous times in past posts. I took the ground lugs apart and all of the contacts look like new, not the slightest indication of corrosion.
When I put a screwdriver across the positive terminal of the starter to the solenoid it clicks as it should.
At this point I am suspicious of the starter but would like to know how I can test it without removing it.
I have read most of your posts and can’t believe the wealth of knowledge you have. My 2001 C5 won’t start. I have a brand new battery that reads 12+ volts until I hook it up to my car. Then the voltage drops to 5-8 volts. When I turn the ignition switch to the on position the dash attempts to light up but flashes like there is a short somewhere. When I try to start the car I get the standard clicking sound from the starter as if the battery is low. I have tried to jump start the car from another vehicle, to no avail. My car has 30,000 miles on it and has always been stored in a heated, dry garage. It has been driven in the rain only a few times, never in snow.
Following is what I have done as a result of your past posts:
I removed the ignition switch, took it apart and found some burned contacts which I cleaned and put the switch back together.
I have checked all of the ground points that have been discussed numerous times in past posts. I took the ground lugs apart and all of the contacts look like new, not the slightest indication of corrosion.
When I put a screwdriver across the positive terminal of the starter to the solenoid it clicks as it should.
At this point I am suspicious of the starter but would like to know how I can test it without removing it.
Advanced
Joined: Dec 2009
Posts: 83
Likes: 0
From: MILLINGTON MICHIGAN
If you are testing the battery out of the car [unconnected to the car] and get 12 volts and then only connect it to the cars electrial and get that kind of drop you have some major short [drain]. It could be the battery but if it load tests ok, you have a short to ground thats active all of the timevs when you use some item [ie like turning something on].
Thread Starter
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Bill,
I have read most of your posts and can’t believe the wealth of knowledge you have. My 2001 C5 won’t start. I have a brand new battery that reads 12+ volts until I hook it up to my car. Then the voltage drops to 5-8 volts. When I turn the ignition switch to the on position the dash attempts to light up but flashes like there is a short somewhere. When I try to start the car I get the standard clicking sound from the starter as if the battery is low. I have tried to jump start the car from another vehicle, to no avail. My car has 30,000 miles on it and has always been stored in a heated, dry garage. It has been driven in the rain only a few times, never in snow.
Following is what I have done as a result of your past posts:
I removed the ignition switch, took it apart and found some burned contacts which I cleaned and put the switch back together.
I have checked all of the ground points that have been discussed numerous times in past posts. I took the ground lugs apart and all of the contacts look like new, not the slightest indication of corrosion.
When I put a screwdriver across the positive terminal of the starter to the solenoid it clicks as it should.
At this point I am suspicious of the starter but would like to know how I can test it without removing it.
I have read most of your posts and can’t believe the wealth of knowledge you have. My 2001 C5 won’t start. I have a brand new battery that reads 12+ volts until I hook it up to my car. Then the voltage drops to 5-8 volts. When I turn the ignition switch to the on position the dash attempts to light up but flashes like there is a short somewhere. When I try to start the car I get the standard clicking sound from the starter as if the battery is low. I have tried to jump start the car from another vehicle, to no avail. My car has 30,000 miles on it and has always been stored in a heated, dry garage. It has been driven in the rain only a few times, never in snow.
Following is what I have done as a result of your past posts:
I removed the ignition switch, took it apart and found some burned contacts which I cleaned and put the switch back together.
I have checked all of the ground points that have been discussed numerous times in past posts. I took the ground lugs apart and all of the contacts look like new, not the slightest indication of corrosion.
When I put a screwdriver across the positive terminal of the starter to the solenoid it clicks as it should.
At this point I am suspicious of the starter but would like to know how I can test it without removing it.
with bmg..Either you have a BAD battery terminal/connection OR that battery is JUNK. Have it LOAD TESTED where you purchased it. and then go from there.
BC
Cruising
Joined: Jul 2008
Posts: 12
Likes: 0
Bill,
I thought all batteries are maintenance free but found out that is not the case. My battery was low on electrolyte and after refilling the cells with distilled water and charging the battery all is OK. Thanks for your help. It's amazing how the simplest things can be the most difficult to figure out sometimes.
Thanks, again
I thought all batteries are maintenance free but found out that is not the case. My battery was low on electrolyte and after refilling the cells with distilled water and charging the battery all is OK. Thanks for your help. It's amazing how the simplest things can be the most difficult to figure out sometimes.
Thanks, again
7th Gear
Joined: Dec 2010
Posts: 7
Likes: 0
Hello everyone Im new here.
Here is my problem I have a 2000 vette just rebuilt the motor and now the abs/tcs lights are on. I have read and checked all the grounds. Here is the codes Im getting. C1234 LR wheel speed circuit open or short. C1242 bpmv pump motor ground ciruit open. C1255 ebtcm internal malfunction. Any ideas that I need to try please let me know. Thank you
Here is my problem I have a 2000 vette just rebuilt the motor and now the abs/tcs lights are on. I have read and checked all the grounds. Here is the codes Im getting. C1234 LR wheel speed circuit open or short. C1242 bpmv pump motor ground ciruit open. C1255 ebtcm internal malfunction. Any ideas that I need to try please let me know. Thank you
Heel & Toe
Joined: Dec 2010
Posts: 22
Likes: 11
From: St George
I just did this to mine - there is no point in just cleaning the lug if your not going to have a close look at the actual contacts and connections - I filled mine with lithium grease - same stuff you put on the hinges - any thick lube will do.
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Instructor
Joined: May 2007
Posts: 201
Likes: 0
From: Peoria Arizona
I also wanted to mark this day as the first time in Corvette ownership (I had a '70 Stingray) where something was not broken or in need of replacement! No codes or non working anything now...for today anyway.
Racer
Joined: Dec 2010
Posts: 250
Likes: 0
Hi Everyone, wanted to post this here too
I got my first vet last month. 2002 coupe 41k miles. always AZ car/ well maintained.
The dealership gave a one month warranty and after one week that was needed to get a new battery. For the next 3 weeks all was well, i watched all gages to know what is normal and what is not.
Go to 2 days past warranty- While driving to work tcs/abs lights come on but by the time i get to work they go off. On the way home they both turn on again but then go off again followed seconds later by TCS coming back on.
It has been like this for a couple weeks now....
Start up in morning- both TCS/ABS lights on for a couple minutes followed by either both lights going off or TCS light coming back on seconds later. Battery volts read over 14 during this time even after warm up
Car driven within a few hours- both lights come on and stay on. Battery volts stay around 13.4. Any electric surge I.E. turn signal, brake lights cause the volts to drop below 13 for a brief couple of seconds. Headlights on can cause the normal reading to stay below 13.2
I took the car to autozone to have alternator checked and they said it was fine.
OH.. when both TCS and ABS are not working neither is my HVAC (dual climate control version) or the power to my rearview mirror/ helper light.
When only TCS is out both HVAC and rearview power work
Here are my codes... When checking sometimes both TCS/ABS lights are on and cause both HVAC and TCS to read no communication.
When the lights are off i get these
pcm- 0135 0155 0161 1133 1153 1571 1689
tcs- 1236 1248 1277 The first 2 tcs are not all the time but often
bcm- 0432
Ipc- U1040
Sdm- U1040
The pcm 1689 is not even on the list and when HVAC is working there is no codes for it.
I have read Bills electric thread and have been able to clean most of my grounds and battery cables but everyone was perfectly clean with no dirt or corrosion.
Any other ideas? Am i missing something with the ground wires? Does this sound like anything anyone has encoutered before?
The dealership gave a one month warranty and after one week that was needed to get a new battery. For the next 3 weeks all was well, i watched all gages to know what is normal and what is not.
Go to 2 days past warranty- While driving to work tcs/abs lights come on but by the time i get to work they go off. On the way home they both turn on again but then go off again followed seconds later by TCS coming back on.
It has been like this for a couple weeks now....
Start up in morning- both TCS/ABS lights on for a couple minutes followed by either both lights going off or TCS light coming back on seconds later. Battery volts read over 14 during this time even after warm up
Car driven within a few hours- both lights come on and stay on. Battery volts stay around 13.4. Any electric surge I.E. turn signal, brake lights cause the volts to drop below 13 for a brief couple of seconds. Headlights on can cause the normal reading to stay below 13.2
I took the car to autozone to have alternator checked and they said it was fine.
OH.. when both TCS and ABS are not working neither is my HVAC (dual climate control version) or the power to my rearview mirror/ helper light.
When only TCS is out both HVAC and rearview power work
Here are my codes... When checking sometimes both TCS/ABS lights are on and cause both HVAC and TCS to read no communication.
When the lights are off i get these
pcm- 0135 0155 0161 1133 1153 1571 1689
tcs- 1236 1248 1277 The first 2 tcs are not all the time but often
bcm- 0432
Ipc- U1040
Sdm- U1040
The pcm 1689 is not even on the list and when HVAC is working there is no codes for it.
I have read Bills electric thread and have been able to clean most of my grounds and battery cables but everyone was perfectly clean with no dirt or corrosion.
Any other ideas? Am i missing something with the ground wires? Does this sound like anything anyone has encoutered before?
Heel & Toe
Joined: Dec 2010
Posts: 22
Likes: 11
From: St George
I'd go over the grounds again or bypass them with a temporary ground. Also I'd take the battery and battery box out and have a very close look at the connections and wiring at the pcm being very careful to check for old repairs that were taped up and hidden from view
Melting Slicks
Joined: Apr 2002
Posts: 2,631
Likes: 2
From: Clever, MO aka SOMO
Here are my codes... When checking sometimes both TCS/ABS lights are on and cause both HVAC and TCS to read no communication.
When the lights are off i get these
pcm- 0135 0155 0161 1133 1153 1571 1689
tcs- 1236 1248 1277 The first 2 tcs are not all the time but often
bcm- 0432
Ipc- U1040
Sdm- U1040
Does this sound like anything anyone has encoutered before?
Thread Starter
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
If it were me and I had all those weird DTCs and fluctuating voltages, I would try and clean the ignition switch contacts. There are most likely a couple of badly carboned up contacts causing low voltages at various times. Give this a try, clear the DTCs and see if it makes an improvement.
-C5 ignition Switch repair -
http://forums.corvetteforum.com/c5-t...ch-repair.html
BC
-C5 ignition Switch repair -
http://forums.corvetteforum.com/c5-t...ch-repair.html
BC
Racer
Joined: Dec 2010
Posts: 250
Likes: 0
If it were me and I had all those weird DTCs and fluctuating voltages, I would try and clean the ignition switch contacts. There are most likely a couple of badly carboned up contacts causing low voltages at various times. Give this a try, clear the DTCs and see if it makes an improvement.
-C5 ignition Switch repair -
http://forums.corvetteforum.com/c5-t...ch-repair.html
BC
-C5 ignition Switch repair -
http://forums.corvetteforum.com/c5-t...ch-repair.html
BC
Racer
Joined: Dec 2010
Posts: 250
Likes: 0
Yay!!!!!!!!!!!!!!!!!!!!!!
You be da man Bill!!!
Took a little under 4 hours total but when i got the ignition apart 2 of the contacts were fried... Way worse than the ones you used as an example.
Used 1000 grit paper and some 90 proof everclear to clean them up which i had on hand
. Did the bends as well to make the contacts tighter.
Cost $0
3 code checks, 6 start ups, and 3 drives sense done
no codes or lights at all
Took a little under 4 hours total but when i got the ignition apart 2 of the contacts were fried... Way worse than the ones you used as an example.
Used 1000 grit paper and some 90 proof everclear to clean them up which i had on hand
. Did the bends as well to make the contacts tighter.Cost $0
3 code checks, 6 start ups, and 3 drives sense done
no codes or lights at all
Thread Starter
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
You be da man Bill!!!
Took a little under 4 hours total but when i got the ignition apart 2 of the contacts were fried... Way worse than the ones you used as an example.
Used 1000 grit paper and some 90 proof everclear to clean them up which i had on hand. Did the bends as well to make the contacts tighter.
Cost $0
3 code checks, 6 start ups, and 3 drives sense done
no codes or lights at all
Took a little under 4 hours total but when i got the ignition apart 2 of the contacts were fried... Way worse than the ones you used as an example.
Used 1000 grit paper and some 90 proof everclear to clean them up which i had on hand
. Did the bends as well to make the contacts tighter.Cost $0
3 code checks, 6 start ups, and 3 drives sense done
no codes or lights at all
Glad to b able to help brother!
Bill
8th Gear
Joined: Apr 2008
Posts: 8
Likes: 0
dead battery
For those of you who have C5's that have problems keeping the battery from going dead if you leave your car idle for a short period of time, here is a procedure that you can use to see if your car is drawing an excessive amount of battery current. The C5 corvette should be able to sit idle for weeks with out running down the battery far enough that it will not start.
If your car has a good battery and it depletes the battery in a few days or a week, use a DC Amp meter to measure the battery current draw when the car has entered the BCM sleep mode.
Once ALL of the cars loads are remove (ie doors shut, trunk shut, interior light off, radar detector and phone chargers removed etc, (make sure that you disconnect the under hood light), disconnect the battery NEGATIVE terminal. Connect a DC AMP METER capable of reading at least 10 amps in SERIES with the NEGATIVE battery terminal and the NEGATIVE battery cable. Once you connect the amp meter into the circuit, he car should power up and enter the "SLEEP MODE" with in a few minutes. It should not take longer than 10-15 minutes. If te car is in the RAP (retained acessory power) mode, it may take that entire 10-15 min to power down.
When you initially connect the AMP meter in the circuit, the current draw will be high. Some where around 8 amps. As the BCM determines that the car is secure, it will start dropping off loads and go into the SECURITY MODE and Sleep Mode. As it drops off loads you will see the battery current drop down from 8 amps to around 2-3 amps them in the milliamp range.
If there is a unwanted load, it could take up to 10-15 min for the current reading to settle out as low as it will go. The target reading will be 15-20 milliamperes. As you can see in the next photo, my 02 ZO6 draws .02 or 20 milliamperes.
With this small current draw and a properly charged battery in good condition, your C5 should be able to sit idle (without a battery tender or battery charger) for at least 3 weeks if not longer. My ZO6 has set idle for 30 days and started normally after that period.
C5's that drain batteries in days or a week have an excessive battery current draw issue. Here are a few places that have proven to be a cause of excessive battery current draw:
Drivers or Passengers seat control multifunction switch. The return spring in the switch gets weak or damaged and the seat sticks in a movement position. The motors are thermally protected by a "circuit breaker" in the passengers foot well and will continuously set and trip until the battery goes dead.
Drivers LUMBAR motor. Same as above!
Interior lights, dash lights, or other interior lights.
Head light motor control module. The module can short inside and draw current even though the lights are down and secure. If you feel the module and its HOT, its bad.
Alternator. The diodes can and do go bad. If hey go bad, the field windings will always be powered and draw current. If you suspect that the alternator is drawing current, remove the field terminal wire from the back of the alternator and insert the AMP Meter in SERIES with the circuit (between the red wire and alternator field terminal). The current draw should be ZERO. If you have current draw, one or more diodes are bad in the alternator. The last alternator that I checked this way was drawing 5 amps.
Bose Amplifier. Theres an amp under the dash on the drivers side dash. The relay for that amp sometimes sticks and the amp remains on even though the car is OFF.
Cell phones, radar detectors, wide band controllers ect... can get left plugged in.
NOTE! If you open the door, or trunk or even remove and then replace a fuse for troubleshooting, it will wake the car up and you will need to wait for it to enter the SLEEP mode again to read the current draw.
If you remove a BCM fuse, it will negate the test because the BCM is controlling the current draw.
Hope this helps figure out the reasons for premature battery failure.
Bill Curlee
If your car has a good battery and it depletes the battery in a few days or a week, use a DC Amp meter to measure the battery current draw when the car has entered the BCM sleep mode.
Once ALL of the cars loads are remove (ie doors shut, trunk shut, interior light off, radar detector and phone chargers removed etc, (make sure that you disconnect the under hood light), disconnect the battery NEGATIVE terminal. Connect a DC AMP METER capable of reading at least 10 amps in SERIES with the NEGATIVE battery terminal and the NEGATIVE battery cable. Once you connect the amp meter into the circuit, he car should power up and enter the "SLEEP MODE" with in a few minutes. It should not take longer than 10-15 minutes. If te car is in the RAP (retained acessory power) mode, it may take that entire 10-15 min to power down.
When you initially connect the AMP meter in the circuit, the current draw will be high. Some where around 8 amps. As the BCM determines that the car is secure, it will start dropping off loads and go into the SECURITY MODE and Sleep Mode. As it drops off loads you will see the battery current drop down from 8 amps to around 2-3 amps them in the milliamp range.
If there is a unwanted load, it could take up to 10-15 min for the current reading to settle out as low as it will go. The target reading will be 15-20 milliamperes. As you can see in the next photo, my 02 ZO6 draws .02 or 20 milliamperes.
With this small current draw and a properly charged battery in good condition, your C5 should be able to sit idle (without a battery tender or battery charger) for at least 3 weeks if not longer. My ZO6 has set idle for 30 days and started normally after that period.
C5's that drain batteries in days or a week have an excessive battery current draw issue. Here are a few places that have proven to be a cause of excessive battery current draw:
Drivers or Passengers seat control multifunction switch. The return spring in the switch gets weak or damaged and the seat sticks in a movement position. The motors are thermally protected by a "circuit breaker" in the passengers foot well and will continuously set and trip until the battery goes dead.
Drivers LUMBAR motor. Same as above!
Interior lights, dash lights, or other interior lights.
Head light motor control module. The module can short inside and draw current even though the lights are down and secure. If you feel the module and its HOT, its bad.
Alternator. The diodes can and do go bad. If hey go bad, the field windings will always be powered and draw current. If you suspect that the alternator is drawing current, remove the field terminal wire from the back of the alternator and insert the AMP Meter in SERIES with the circuit (between the red wire and alternator field terminal). The current draw should be ZERO. If you have current draw, one or more diodes are bad in the alternator. The last alternator that I checked this way was drawing 5 amps.
Bose Amplifier. Theres an amp under the dash on the drivers side dash. The relay for that amp sometimes sticks and the amp remains on even though the car is OFF.
Cell phones, radar detectors, wide band controllers ect... can get left plugged in.
NOTE! If you open the door, or trunk or even remove and then replace a fuse for troubleshooting, it will wake the car up and you will need to wait for it to enter the SLEEP mode again to read the current draw.
If you remove a BCM fuse, it will negate the test because the BCM is controlling the current draw.
Hope this helps figure out the reasons for premature battery failure.
Bill Curlee
1st Gear
Joined: Jan 2011
Posts: 1
Likes: 0
I have a 2000 corvette and I think I have the same ground issues. ABS and traction controll light will come on when the car is first started and may stay on for up to 30 minutes. While these lights are on the power to the heater controlls will not come on.......no heat, no ac, no fan.
When I read this post I thought this could be my problem..Gonna take it apart first thing in the morning.
THANKS OK CLEANED ALL GROUNDS DID NOT FIX THE ISSUES. SO I WENT TO THE IGNITION IT WAS IN BAD SHAPE A LITTLE 400 GRIT FIXED IT. ALL LIGHTS ARE OFF AND THE HEAT WORKS .THANKS TO THIS PAGE AND YOUR KNOWLEDGE YOU SAVED ME A LOT OF MONEY. THANKS I LOVE YOU GUYS
When I read this post I thought this could be my problem..Gonna take it apart first thing in the morning.
THANKS OK CLEANED ALL GROUNDS DID NOT FIX THE ISSUES. SO I WENT TO THE IGNITION IT WAS IN BAD SHAPE A LITTLE 400 GRIT FIXED IT. ALL LIGHTS ARE OFF AND THE HEAT WORKS .THANKS TO THIS PAGE AND YOUR KNOWLEDGE YOU SAVED ME A LOT OF MONEY. THANKS I LOVE YOU GUYS
Last edited by Donnie1972; Feb 4, 2011 at 10:23 PM.
Le Mans Master
Joined: Dec 2006
Posts: 7,251
Likes: 16
From: Phoenix Arizona
Bad brakes...headlight wiring bad!
Here is a strange one. I was getting intermittent brake failure at high speeds on the track, really sucked, couple times i went off track 
and no codes!
Putting the car back to street tires I noticed my left headlight was yellow/dim. i messed with the wire connection near the headlights and the headlight got bright again. Next time at the track, brakes worked great!
Hope this helps others
and no codes!Putting the car back to street tires I noticed my left headlight was yellow/dim. i messed with the wire connection near the headlights and the headlight got bright again. Next time at the track, brakes worked great!
Hope this helps others
Thread Starter
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Here is a strange one. I was getting intermittent brake failure at high speeds on the track, really sucked, couple times i went off track and no codes!
Putting the car back to street tires I noticed my left headlight was yellow/dim. i messed with the wire connection near the headlights and the headlight got bright again. Next time at the track, brakes worked great!
Hope this helps others
and no codes!Putting the car back to street tires I noticed my left headlight was yellow/dim. i messed with the wire connection near the headlights and the headlight got bright again. Next time at the track, brakes worked great!
Hope this helps others
Which connector did you move? The one in the picture?
