Erratic Problems

[db21]

Have a 99, 3.4L Alero. Just replaced LIM and Head gasket and everying was going fine for a few hundred km's...then started getting dash lights come on and engine won't start up.

ABS lights come on and trac light and odometer lights flicker but engine runs and shifts fine. You turn off the engine and it will not restart - nothing at all, no power. You disconnect the battery and it will restart and run okay...until it happens again. Have also had the parking brake light come on with the ABS and track lights as well? And today was driving and the engine just turned off on the highway...got it restarted though. But when I got to work lights were back on again, and odometer flashing. Stopped car turned it off then turned it on and nothing...

Any ideas...thinking something is shorting out (this flickering odometer), and then computer is tripped out and will not reset until battery is disconnected. Not sure where to start looking though. Wondering if it could be related to the work I did, or if it is something new...Not sure if the ABS lights are an indication of where the problem is or is a random fault light due to a short or bad computer?

I see lots of folks having issues with trac light, and shifting, but my shifiting and engine are running good now...just some flacky electronics.

Appreciate thoughts on what might be going on here...would a short in the ABS sensor trip my computer??? Why would parking light come on? Or odometer light flicker? HELP!!! Many thanks!

[BNaylor]

To start check your battery and the alternator output. Make sure voltage output is good verified with a DMM. Check all battery terminals and cable connections.

As far as the ABS and Traction Control system problems you may need to get it scanned with an ABS capable scanner.

[db21]

DMM - digital multimeter?

Battery is fine, cranks over no problem. Have gone over all connections, but will do it again.

I took at the ABS main fuse to see if I could eliminate the sensors as the source of the problem. Still got erratic behavior from low trac and trac off lights....and the odometer light flickered too. Although this time it didn't seem to lock out the computer after I turned it off, I could restart.

Will go over all connections, remove some more ABS fuses, there area few in there, and check output from alternator. Although I've got good power to all accessories, radio, fan, lights etc...I would think the dash light and led powering the odometer is the lowest voltage items, so don't think it could be alternator...

[BNaylor]

That is correct. It is always good to verify with a meter because the PCM module looks at the 12 volts and has a sense circuit to insure the voltage is within parameters otherwise it will tilt. That way you can rule it out and look at other possible causes. Across the battery negative and positive terminals you should get around 12-14 volts (ballpark) while engine is running at idle.

[sbkins00]

Hey, I have a 99 Alero that developed very strange electrical problems. Sometimes the gauges would just stop working, sometimes it wouldn't start, so I broke down and took it to the dealer. There was water getting into the fuse panel on the inside of the drivers door. After a new fuse box and some silicone, no more electrical problems!