Brakes draining my battery

Series I L27 (1992-1994 SE,SLE, SSE) & Series II L36 (1995-1999 SE, SSE, SLE) and common problems for the Series I and II L67 (all supercharged models 92-99) Including Olds 88's, Olds LSS's, Olds 98 91-96, Buick Lesabres and Park Avenue 91-96. Please use General Chat for non-mechanical issues, and Performance and Brainstorming for improvements.
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Mitchell77
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Brakes draining my battery

Post by Mitchell77 »

So my abs light came on to days ago. So I clean the sensor and the ground wire to it and the abs light went off and came back on... so the cleaning didn't help it.
I also noticed when I use my reverse gear or my brakes for the matter the battery voltage drops ..... is this a familiar problem withe the bonnies..... anyone??
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Sirius
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Re: Brakes draining my battery

Post by Sirius »

Your ABS module is probably bad. That happened on my old 93 SSE and I just drove it like that. If that's the case, your brakes still work fine, you just won't have antilock brakes - you'll have to pump them on ice or snow.

Your brakes aren't draining your battery. Your voltage source is weak (bad battery, bad alternator, bad cable...something) so when you light up the brake lights or reverse lights it takes a toll on your source. Are there any aftermarket accessories on your car? Remote starter, alarm system, sound system, etc.? If so, I'd start there.
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acg_93_ssei
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Re: Brakes draining my battery

Post by acg_93_ssei »

Sirius wrote:Your brakes aren't draining your battery. Your voltage source is weak (bad battery, bad alternator, bad cable...something) so when you light up the brake lights or reverse lights it takes a toll on your source. Are there any aftermarket accessories on your car? Remote starter, alarm system, sound system, etc.? If so, I'd start there.
I'll second that. Given the history of problems with your car that you have provided in several other posts here, I think your chief problem right now is that your car is running undervoltage because the alternator is not properly charging the battery and maintaining system voltage while you're driving. The electronics in your car can go a little bonkers if they're not getting a full 12-14 volts. The fact that your voltmeter shows a noticeable drop when your brake lights or backup lights go on means that the electrical system is not holding up its end.

If I remember right, your alternator bench-tested as good when out of the car, and I think your battery did also...? The next step would be to test whether the battery is getting charging amperage while the car is running. My guess is that it is not, and that the car is actually running on the battery until it dies, after which someone jump-starts it, the battery recovers quickly during the jump-start (because it's actually a good battery), and the whole process repeats.
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J Wikoff
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Re: Brakes draining my battery

Post by J Wikoff »

My abs light came on lots of years ago. The dealer told me it needed a wheel bearing (that has the sensor built in) and an abs module. I just ignored it for a long time and didn't have abs. I replaced that wheel bearing while doing other stuff several years ago, and lo & behold the light went away and the abs has worked fine ever since. Not sure what kind of scanner is needed for ABS on a 98, but it might be worth getting that done. Auto parts places might even be able to scan it for free.
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Mitchell77
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Re: Brakes draining my battery

Post by Mitchell77 »

acg_93_ssei wrote:
Sirius wrote:Your brakes aren't draining your battery. Your voltage source is weak (bad battery, bad alternator, bad cable...something) so when you light up the brake lights or reverse lights it takes a toll on your source. Are there any aftermarket accessories on your car? Remote starter, alarm system, sound system, etc.? If so, I'd start there.
I'll second that. Given the history of problems with your car that you have provided in several other posts here, I think your chief problem right now is that your car is running undervoltage because the alternator is not properly charging the battery and maintaining system voltage while you're driving. The electronics in your car can go a little bonkers if they're not getting a full 12-14 volts. The fact that your voltmeter shows a noticeable drop when your brake lights or backup lights go on means that the electrical system is not holding up its end.

If I remember right, your alternator bench-tested as good when out of the car, and I think your battery did also...? The next step would be to test whether the battery is getting charging amperage while the car is running. My guess is that it is not, and that the car is actually running on the battery until it dies, after which someone jump-starts it, the battery recovers quickly during the jump-start (because it's actually a good battery), and the whole process repeats.
:btruestory: ur right
My red wire was cut in half on the harness to the alternator.
So I attempted to repin it from alternator to the pcu ....but the harnesses to the pcm have a bolt and washer connection
So I left it alone and spliced the alternator wire to find out.... my red wire to my alternator in corroded throughout the installation... so i clean about inch and connected at splice as planted..not sure how far the corrosion is but I'm jus gonna replace the engine harness for the 2nd time, I'm hoping it works. Gages haves been reading good and battery hold but it still jumps a bit when braking or when alternator does its charge cycles. :sucks:
Mitchell77
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Re: Brakes draining my battery

Post by Mitchell77 »

J Wikoff wrote:My abs light came on lots of years ago. The dealer told me it needed a wheel bearing (that has the sensor built in) and an abs module. I just ignored it for a long time and didn't have abs. I replaced that wheel bearing while doing other stuff several years ago, and lo & behold the light went away and the abs has worked fine ever since. Not sure what kind of scanner is needed for ABS on a 98, but it might be worth getting that done. Auto parts places might even be able to scan it for free.
I got thr abs light off. :banana:
Mitchell77
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Re: Brakes draining my battery

Post by Mitchell77 »

Sirius wrote:Your ABS module is probably bad. That happened on my old 93 SSE and I just drove it like that. If that's the case, your brakes still work fine, you just won't have antilock brakes - you'll have to pump them on ice or snow.

Your brakes aren't draining your battery. Your voltage source is weak (bad battery, bad alternator, bad cable...something) so when you light up the brake lights or reverse lights it takes a toll on your source. Are there any aftermarket accessories on your car? Remote starter, alarm system, sound system, etc.? If so, I'd start there.
Bad alternator connection.. ur rt
The red wire was bad
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