Ah, car electrical problems

Matthew K

Line Up and Wait
Joined
Sep 14, 2016
Messages
788
Location
Georgia
Display Name

Display name:
Broke Engineer
Ok so a member of my family has a 2005 Buick Lacrosse CXL. Has owned it since new.

Battery went bad in it a few weeks ago, a family member replaced the battery for them.

New battery went dead, not sure if its just because the new battery didn't have much of a charge and it sitting hooked to the car for a couple weeks killed it, or if there's something draining it.

That's not the question though. I went to check on the car yesterday, put the new battery on the charger for about an hour, then jumped the car off as the hour of charging wasn't quite enough.

Car *barely* started when I jumped it, voltage I imagine dropped pretty low while turning the engine over.

Upon getting the car started, I notice the instrument cluster isn't working. It worked before this battery issue. I let the car run for awhile, it was charging the battery right at 14.5 volts. 10 mins go by and I turn the car off, unhook the battery to let the computer reset and hopefully fix the instrument cluster. No joy. Battery started car back up, so its holding a charge, at least in the short term.

Checked the fuses under the hood of the car and their all good. Made sure the cables are hooked to the battery securely, but instrument cluster still not working. No tach, speedometer, gas, or temp. Backlight works, and if I hit the trip button the mileage displays for a few seconds then disappears.

Could a super low voltage when trying to start the car have caused damage to this cluster? Or perhaps a voltage surge when the car started from havings its own alternator going along with the jump cars?
 
The cluster could be the problem. I think there is common problem on some GM cars where a bad cluster can have a parasitic battery drain.

There are some videos on Youtube.
 
Could a super low voltage when trying to start the car have caused damage to this cluster?
Doubtful. But remember a 12 volt battery is considered dead below 12-11.5v depending who you listen too. If the new battery has not been permanently damaged by it's last discharge, put it on a good battery charger for 24 hours then measure it's resting voltage. Should be 12.6 to 12.8 avg. Then with clean connections connect battery and check cluster. If still no go then Youtube as mentioned as every vehicle is different. But you should still check for the battery drain unless you want to replace batteries every month.;)
 
Test the voltage at the battery terminals with a voltmeter if you have one. I wouldn't trust the car's voltage readout. Test both off, and while running.
 
Is the alternator doing it's job? Also, what length of trip does she make?

We live in the city very close to work and school, and almost all of our trips are < 4mi one way. That is not enough driving for the alternator to replace the charge lost due to starting the engine. As such, I found that our batteries were lasting 2 years max, so after the last group of battery swaps, I'm now putting each car on the charger every weekend. It sometimes takes 8-9 hours[1] on the charger to get the battery fully charged.

Just food for thought.

[1] Wife and daughters cars, as not only are the drives short, but all winter they have the seat heaters on ROAST, which just sucks the zots out of the batteries all the quicker.
 
With the car off, connect an ammeter in the positive battery line. Use your multimeter. I bet there's a significant drain going on. Start pulling fuses out one at a time until the drain suddenly stops, and now you have the bad circuit.

Edit: I was gently reminded that one should put the ammeter in the negative (ground) lead, to avoid having a wrench shorting against the body or some other grounded part.
 
Last edited:
I hate these electrical issues. I had a Nissan Xterra that I finally had to remove all the door open/close switches cause the anti-theft alarm would just go off randomly. All those . Never did find the actual problem
 
Measure the parasitic drain with an ammeter. Make sure the door, trunk, and underhood lights are all off. On modern cars you need to wait as much as 45 minutes for all modules to go to sleep. 50mA is a reasonable limit in the absence of specific manufacturer's data.
 
GM’s have a history of the delco anti-theft radios going bad and draining power. I'd start there. The needles on the cluster is a good sign that the battery has been disconnected. If that passes, check the alternator. I’d be willing to bet there’s parasitic drain somewhere in the system.
 
Test the voltage at the battery terminals with a voltmeter if you have one. I wouldn't trust the car's voltage readout. Test both off, and while running.
Agreed. That's what I've been doing. Not even sure that there's a way for the car to display voltage for this year model.
The cluster could be the problem. I think there is common problem on some GM cars where a bad cluster can have a parasitic battery drain.

There are some videos on Youtube.
If so, that'll kill two rocks with one stone.
Is the alternator doing it's job? Also, what length of trip does she make?

We live in the city very close to work and school, and almost all of our trips are < 4mi one way. That is not enough driving for the alternator to replace the charge lost due to starting the engine. As such, I found that our batteries were lasting 2 years max, so after the last group of battery swaps, I'm now putting each car on the charger every weekend. It sometimes takes 8-9 hours[1] on the charger to get the battery fully charged.

Just food for thought.

[1] Wife and daughters cars, as not only are the drives short, but all winter they have the seat heaters on ROAST, which just sucks the zots out of the batteries all the quicker.
It doesn't get driven lol. Alternator works, car just doesn't get driven. That's why I'm not quite sure if its parasitic drain yet as the car just sat there for 3 weeks without being rain with the new battery (of which I don't know the voltage when it was installed, as someone else installed it)


That's not the main point of the thread though, I know what to do regarding finding parasitic drain, I'm looking for insight on this gauge cluster not working right after this battery problem.
 
Last edited:
GM’s have a history of the delco anti-theft radios going bad and draining power. I'd start there. The needles on the cluster is a good sign that the battery has been disconnected. If that passes, check the alternator. I’d be willing to bet there’s parasitic drain somewhere in the system.
Could be something similar to this. I saw someone else mentioning that the switch that gives power to the stereo speakers can get stuck on and drain the battery. Short of some corrosion being somewhere (which I don't think there is), the next thing I'd assume would be radio issues.
 
I hate these electrical issues. I had a Nissan Xterra that I finally had to remove all the door open/close switches cause the anti-theft alarm would just go off randomly. All those . Never did find the actual problem
Rats also make things fun. I've got an 83' f100 that had a rat/mouse bite into some of the wires and had various electrical issues bc of it(mostly solved now). The 83' fords have just enough electronics on it for it to be annoying.
 
Back
Top