Should Volt Meter zero-out when key off?
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From: Florida
Should Volt Meter zero-out when key off?
Was just showing-off my Auto Meter guages to a friend and he noticed that the Volt Meter was NOT @ zero when the key was off...should it be?
I had previously had a problem w/ a slow drain on the battery, but since I replaced all the fusebox-forward wiring (Lectric Limited), I haven't noticed it. I did notice that the Volt Meter now reads about 14V, whereas prior to the wiring replacement, it hovered around 12.5V.
btw: '76 w/ '95 LT1/4L60e
Thanks
I had previously had a problem w/ a slow drain on the battery, but since I replaced all the fusebox-forward wiring (Lectric Limited), I haven't noticed it. I did notice that the Volt Meter now reads about 14V, whereas prior to the wiring replacement, it hovered around 12.5V.
btw: '76 w/ '95 LT1/4L60e
Thanks
Burning Brakes
Joined: Jan 2006
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From: Same as our leaders Out of my mind
Hi , your volt meter should zero - out when the key is off. If you suspect a circuit - such as the volt meter - is drawing current when it should not, just pull the related fuse out and isolate the suspect circuit. If you have the old style glass tube fuses, you may even notice a tiny spark when the fuse touches the contacts - which indicates that there is current flowing. A second idea is to remove one of the battery terminals and observe the volt meter. If the volt meter does not zero out with the battery disconnected, then I would assume that this is a "normal" response for the new gauge and the same as when the ignition switch is off.
Last edited by icanfixitforyou; Feb 3, 2006 at 03:13 PM.
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From: Florida
Good suggestions "icanfixitforyou"...Thanks!
I just pulled the fuse for the gauges and no movement of the Volt Meter. I haven't yet tried removing a battery cable as I do NOT want to reset all my stations, clock, and reprogram all my CD titles back in, but if I have to....
Before I contact AutoMeter, can anyone confirm that the AutoMeter Volt Meter does or does not zero-out when the key is turned off?
BTW: will those 9-volt "reverse-powering" adaptors (plug into cig lighter) work on C3's to keep the radio stations, clock, etc.. from losing their memory when the Bat is disconnected? I've only seen them advertised for C4 and up...wondered why C3 are not mentioned???
EDIT: YES, those 9V adaptors do work...disconnected the Bat(+) and radio presets/time/cd titles stayed in memory!
Thanks!
I just pulled the fuse for the gauges and no movement of the Volt Meter. I haven't yet tried removing a battery cable as I do NOT want to reset all my stations, clock, and reprogram all my CD titles back in, but if I have to....
Before I contact AutoMeter, can anyone confirm that the AutoMeter Volt Meter does or does not zero-out when the key is turned off?
BTW: will those 9-volt "reverse-powering" adaptors (plug into cig lighter) work on C3's to keep the radio stations, clock, etc.. from losing their memory when the Bat is disconnected? I've only seen them advertised for C4 and up...wondered why C3 are not mentioned???
EDIT: YES, those 9V adaptors do work...disconnected the Bat(+) and radio presets/time/cd titles stayed in memory!
Thanks!
Last edited by DR76; Feb 5, 2006 at 02:20 PM. Reason: typo
Le Mans Master
Joined: Jan 2006
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From: Boca Raton Florida
it might work to keep your stations, but I would think it would mask the problem when you disconnect the battery terminal. The voltmeter would simply read the 9v battery instead of the car battery. But, you still might see it jump. Either way, the Voltmeter will not be the culprit draining your battery, it is after all controlled by a switch or relay, THERE will be the problem
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From: Florida
Originally Posted by SIXFOOTER
the Voltmeter will not be the culprit draining your battery, it is after all controlled by a switch or relay, THERE will be the problem
Thanks!
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From: Florida
Batman: I "think" I need to clarify... By Volt Meter, I'm refering to the In-Dash AutoMeter Volt Meter, not a hand-held volt meter used to check current. I think that w/ the key "off" there shouldn't be any reading on the In-Dash Volt Meter regardless of courtesy lights being on or not...correct?
Sorry for the confusion...
Here's a pic of gauges w/ key "off"
Sorry for the confusion...
Here's a pic of gauges w/ key "off"
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Burning Brakes
Joined: Jan 2006
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From: Same as our leaders Out of my mind
I had this problem with an old 66 GMC pick up truck I had. The analog factory voltmeter always read battery voltage even if the ignition was switched off. If I left the truck for more than 2-3 days it would drain the battery. My solution was to disconnect the battery terminal when planning to store the truck for any length of time.
Some gauges will stay "at rest" wherever they were at their last reading, others will zero out, that is why I suggested disconnecting the battery, so you can see what your gauge does when there is absolutely no voltage anywhere in the system. It may be a pain in the rear, but not in the wallet. Your only investment is your time. Good luck with the troubleshooting!
Some gauges will stay "at rest" wherever they were at their last reading, others will zero out, that is why I suggested disconnecting the battery, so you can see what your gauge does when there is absolutely no voltage anywhere in the system. It may be a pain in the rear, but not in the wallet. Your only investment is your time. Good luck with the troubleshooting!
Le Mans Master
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From: Las Vegas - Just stop perpetuating myths please.
I have to compliment u for that AutoMeter upgrade - really got the modern look. 
Now i don't know if the '76 had a voltmeter or ammeter. My '74 has an ammeter but my Zip cataloge dosen't say what a '76 uses though the '77 and later use voltmeters.
Anyways by now u should understand the gauge wiring better than most and can find the correct wire to measure with a hand held voltmeter. Voltmeter gauges measures the alt output and is switch through ign sw. So try and measure the gauge wires with ign off.
But if original gauge was an ammeter then the wiring will not work for a voltmeter - u will need to wire in ur own. Ammeter measures voltages across a very low resistance shunt found in the batt + cabling.
So check the actual voltage at the gauge terminals or the connecting wires to see if some potential is there with ign sw off or the gauge just off zero calibration - which makes sense of ur first post reporting an increase in normal voltage reading.
BTW i used Lectric Limited too for wtr temp sensor and it works great as i recently had my all my gauges calibrated by Corvette Instruments in Florida for only 'bout $150.
Good luck and post ur results.
cardo0
Now i don't know if the '76 had a voltmeter or ammeter. My '74 has an ammeter but my Zip cataloge dosen't say what a '76 uses though the '77 and later use voltmeters.
Anyways by now u should understand the gauge wiring better than most and can find the correct wire to measure with a hand held voltmeter. Voltmeter gauges measures the alt output and is switch through ign sw. So try and measure the gauge wires with ign off.
But if original gauge was an ammeter then the wiring will not work for a voltmeter - u will need to wire in ur own. Ammeter measures voltages across a very low resistance shunt found in the batt + cabling.
So check the actual voltage at the gauge terminals or the connecting wires to see if some potential is there with ign sw off or the gauge just off zero calibration - which makes sense of ur first post reporting an increase in normal voltage reading.
BTW i used Lectric Limited too for wtr temp sensor and it works great as i recently had my all my gauges calibrated by Corvette Instruments in Florida for only 'bout $150.
Good luck and post ur results.
cardo0
Le Mans Master
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From: Boca Raton Florida
Hey Dr, you read my post correctly. The Guages are not "on" all the time, thats why they Zero when the ignition is switched off, they are switched thru the Ign circuit somewhere. Cardo) is correct, if your car was originally with an Amp meter it will not work as a volt meter with the otiginal wiring, easy fix, just take the - side of the meter to a ground. Good Luck
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From: Florida
My apologies... was not thinking of the ignition as a "switch", but it sure is!
Yes, I originally had an ammeter, so let me try relocating the "-" side to ground as suggested.
Might be a day or two (or three) until I get to this, but will post my results (good or bad).
Also thanks for the compliment... everyone seems to like the Autometers, (and did those clocks ever work?) I think the tranny temp gauge is much more useful!
Thanks again everyone
Yes, I originally had an ammeter, so let me try relocating the "-" side to ground as suggested.
Might be a day or two (or three) until I get to this, but will post my results (good or bad).
Also thanks for the compliment... everyone seems to like the Autometers, (and did those clocks ever work?) I think the tranny temp gauge is much more useful!
Thanks again everyone
Thread Starter
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Joined: Jun 2001
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From: Florida
OK, so I'm the Big Dummy! Did not realize that the pos(+) going to the original ammeter was not going thru the gauge fuse (and therfore, always "hot"). I just "piggybacked" off one of the other hot wires going to the other gauges...now Volt Meter zeros-out as it should... 
I guess I just haven't let the car sit long enough since replacing the engine and lighting harnesses, as I haven't have a battery issue since doing so. At least it wasn't a wasted purchase...those 30+ year-old wires were in pretty bad shape and I'm MUCH more comfortable knowing that an underhood fire is much LESS likely!
Thanks again...one less thing to worry about!
I guess I just haven't let the car sit long enough since replacing the engine and lighting harnesses, as I haven't have a battery issue since doing so. At least it wasn't a wasted purchase...those 30+ year-old wires were in pretty bad shape and I'm MUCH more comfortable knowing that an underhood fire is much LESS likely!
Thanks again...one less thing to worry about!