Gauges & electrical intermittent problem

[jr6078]

I have a 99 Alero GLS 3.4L with 137700 miles. A strange problem has started to develop, and I've found some posts with some possibly related issues, nothing seems to fit this problem exactly.

The other day, I started the car and after it was running for a few seconds, all the dash lights came on for about a second and then went off. Since then, when I start the car, occasionally none of the gauges work (tach, speedo, fuel, temp), the lights don't work, windows don't operate, and none of the interior electrical functions will work (radio, blower, etc), but the car still runs.

If I shut it off and restart it, the problem usually goes away, but sometimes it takes two or three attempts. Today, I noticed that I could "anticipate" the problem before I even start the car, because when I turn the key to the "on" position before going to start, the fuel and temp gauges won't move if the problem is there.

I haven't had a chance to check anything, and I'm at somewhat of a loss as to where to start.

Any input is appreciated.

[Iflylow]

It sounds like either an ignition switch going bad, or the BCM.
Bad ignition switches cause all sorts of weird electrical issues, and so do bad BCMs. Both are fairly common problems.
Hope it is the BCM, because then it will only be about $250, ignition switches are more I think.

[jr6078]

Thanks for the input...

I was thinking that either of those may be possibilities, but I've also read a couple of threads that indicated that an alternator that's going bad can cause the gauges to do wierd things. I just wonder if an alternator that's going this direction would fail a test, especially where it's an intermittent thing at this point.

[xeroinfinity]

I would also check your battery and ground terminals and the power wire on your under hood fusebox.

If those are clean and tight and your battery is fully charged then it could possibly be your ignition switch.

[jatzarik]

i've got the exact same problem... i can turn headlights on manually... my guess is ignition switch b/c while my dash was out i my passlock was acting up (not uncommon for me) but i could not see security light blinking. I decided to wait 10 minutes... in the mintue of the wait, guages started working and there was the security light blinking and it finished its 10 mintues and away i went. I could be wrong, but wouldn't the security light cycle not being interrupted indicate that the BCM was finctioning properly.

[xeroinfinity]

Originally Posted by Iflylow

It sounds like either an ignition switch going bad, or the BCM.
Bad ignition switches cause all sorts of weird electrical issues, and so do bad BCMs. Both are fairly common problems.
Hope it is the BCM, because then it will only be about $250, ignition switches are more I think.

A new BCM is around $400 + a relearn procedure, ignition switch is about the same...from the stealership.

Also if the BCM is bad, your SVS light will be on constantly with a P1610 DTC , or other simular DTC, being a serial data communications errors and your ICP usualy works fine.

BTW jr6078, you have checked ALL the fuses ?
Also thiers a procedure here for testing the ignition switch, here is the link.

Good Luck

[jr6078]

Thanks to all for your input...

I've discovered a couple of other things about the problem, but still no closer to a solution. I still haven't had a chance to do much in the line of troubleshooting. I have discovered that really only four things don't work when this happens...the instrument cluster is gone completely, the heater/ac blower, the automatic lights and the door window switches. Everything else that I can see is working. I can manually turn on the lights, the radio works, the turn signals work and the wipers work. I've also had it happen a few times now, that all this will drop out while I'm driving, and then will all come back on after a few minutes. So, I'm wondering if maybe there's a relay that's common to these items that may be weak and intermittently making and losing contact??

Again, thanks for the input, and I'll let you know if I find anything. In the meantime, if you all think of anything else, I'm still open to suggestions.

[jr6078]

Gremlins...gotta love em'

Well, the other day, it started throwing codes and the SES light came on. I'm pretty sure the codes were bogus and unrelated to the problem (O2 sensor and Evap vent valve/purge solenoid). I erased the codes, and drove another day, with the same problem intermittently occurring. Yesterday, it threw some more codes.

Today, I pulled the ignition switch and tested it. Tested good, so I re-installed it and the problem was gone and so was the SES light.

I must have re-connected something that had developed a poor connection, or my ignition switch is going bad and I just got lucky for now. At least I have a good idea about what it's most likely to be in the event the gremlins should decide to re-appear...

Thanks again for all the input and help.