UPDATE: It was the alternator causing the battery light to come on. More updates found below in post #11.
TL;DR
Car has 192,922 miles on it.
Car randomly doesn't start, been going on for months, tried new battery and new battery clamps, didn't help
Did a test and found out the PCM/instrument cluster circuit has a parasitic draw
Battery light started coming on and off randomly a few weeks ago
Been having problems getting the car to start. Sometimes it starts, sometimes it doesn't. And even when it does start, sometimes I have to turn the key and keep it there for a few seconds until the car starts up. Not because of weak cranking, just would go from nothing to firing up regularly.
Replaced the battery wire clamps since they were original and they weren't as tight as they could have been. Still had the problem. Put a new battery in, still had the problem.
Since then, my battery light randomly comes on now (started a few weeks ago, long after the initial car not starting problem). It will go off after being on for several minutes. It usually comes on 5-10 minutes after driving. Other than that, no other noticeable patterns.
Figured a wire may be loose, but hitting bumps vs smooth roads doesn't affect the light plus it comes on when the car is sitting still (although I guess vibration could be a culprit). Just seems to come on and off whenever it wants. Was just in my garage troubleshooting and it came on then went off after a minute. Then a minute later came on again until I turned my car off 5 minutes later.
I also have a draw on the battery. After hooking up a testing light, found out it's the 40 amp fuse that controls the instrument cluster and PCM.
So the car not starting sometimes would appear to be because of the parasitic drain. But, doesn't explain the battery light coming on. Which points to the alternator and it's just a coincidence that it's happening while having the car not starting problems. Although again, the not starting problem has been around for months, long before the light ever came on.
Just did some voltage testing:
Engine Running - 13.9
Turned headlights on - 13.8
Battery light came on - 13.8
12.5 when fans kicked on and then 12.2...headlights, ac, and rear defroster were on at this point as well.
Fan went off and went to 12.5
Let car run a few minutes and turned it off at 12.6.
After sitting for a little it drops to 12.2-12.3 which is why, I'd assume, it has trouble starting.
I currently have the fuse pulled that was drawing power, going to check the voltage tonight after it sits for a few hours. If it's at 12.6 then I know it was drawing enough power to not start the car.
ADDITIONAL NOTES:
My meter doesn't have DC amps so I couldn't test the amount of parasitic draw.
When driving, the battery light will go back off after a bit.
I still need to crawl under the car and make sure the wires going to the alternator aren't loose.
I took the kick panel off to get access tot eh PCM and made sure no wires were loose, which they didn't appear to be. But besides that, I have no idea what to do/look for.
I also have a slight misfire I've been trying to figure out/fix. Maybe that's related to all of this...not getting enough voltage/power?? Alternator?
QUESTIONs:
If the alternator is going bad, it's still a possibility that it will charge the battery at some times but not others?
Since the PCM and instrument cluster are drawing power when the car is off, does this mean one of them is bad? Or is there something else I can do to test things?
Hate to think about it, but I'm thinking my alternator is on it's last leg. This would be #4 or so, I lost count.
TL;DR
Car has 192,922 miles on it.
Car randomly doesn't start, been going on for months, tried new battery and new battery clamps, didn't help
Did a test and found out the PCM/instrument cluster circuit has a parasitic draw
Battery light started coming on and off randomly a few weeks ago
Been having problems getting the car to start. Sometimes it starts, sometimes it doesn't. And even when it does start, sometimes I have to turn the key and keep it there for a few seconds until the car starts up. Not because of weak cranking, just would go from nothing to firing up regularly.
Replaced the battery wire clamps since they were original and they weren't as tight as they could have been. Still had the problem. Put a new battery in, still had the problem.
Since then, my battery light randomly comes on now (started a few weeks ago, long after the initial car not starting problem). It will go off after being on for several minutes. It usually comes on 5-10 minutes after driving. Other than that, no other noticeable patterns.
Figured a wire may be loose, but hitting bumps vs smooth roads doesn't affect the light plus it comes on when the car is sitting still (although I guess vibration could be a culprit). Just seems to come on and off whenever it wants. Was just in my garage troubleshooting and it came on then went off after a minute. Then a minute later came on again until I turned my car off 5 minutes later.
I also have a draw on the battery. After hooking up a testing light, found out it's the 40 amp fuse that controls the instrument cluster and PCM.
So the car not starting sometimes would appear to be because of the parasitic drain. But, doesn't explain the battery light coming on. Which points to the alternator and it's just a coincidence that it's happening while having the car not starting problems. Although again, the not starting problem has been around for months, long before the light ever came on.
Just did some voltage testing:
Engine Running - 13.9
Turned headlights on - 13.8
Battery light came on - 13.8
12.5 when fans kicked on and then 12.2...headlights, ac, and rear defroster were on at this point as well.
Fan went off and went to 12.5
Let car run a few minutes and turned it off at 12.6.
After sitting for a little it drops to 12.2-12.3 which is why, I'd assume, it has trouble starting.
I currently have the fuse pulled that was drawing power, going to check the voltage tonight after it sits for a few hours. If it's at 12.6 then I know it was drawing enough power to not start the car.
ADDITIONAL NOTES:
My meter doesn't have DC amps so I couldn't test the amount of parasitic draw.
When driving, the battery light will go back off after a bit.
I still need to crawl under the car and make sure the wires going to the alternator aren't loose.
I took the kick panel off to get access tot eh PCM and made sure no wires were loose, which they didn't appear to be. But besides that, I have no idea what to do/look for.
I also have a slight misfire I've been trying to figure out/fix. Maybe that's related to all of this...not getting enough voltage/power?? Alternator?
QUESTIONs:
If the alternator is going bad, it's still a possibility that it will charge the battery at some times but not others?
Since the PCM and instrument cluster are drawing power when the car is off, does this mean one of them is bad? Or is there something else I can do to test things?
Hate to think about it, but I'm thinking my alternator is on it's last leg. This would be #4 or so, I lost count.
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