94 Bonne Starting problems - electrical - very strange

[CentralOR]

I've read a number of the threads regarding starting issues with the Bonnevilles and so far I haven't seen anything that quite describes the issues I'm having with my '94 Bonneville SE.

I just purchased this vehicle in Portland and initially everything seemed fine. It ran fine all the way to Redmond - but after stopping at the store it didn't want to start. We towed it back home and I managed to get it started after I cleaned up the battery terminals. I figured that must have been the problem.

I went ahead and drove it to work the next day and on the way home it died again. I went ahead and replaced the positive battery cable and it started alright but just long enough to get out of the driveway for a test drive.

It seems to have two conditions - one where it starts and everything seems to function alright. And the other when it won't start and the electrical equipment doesn't function properly. When it won't start if I try to move the power seat all the interior lights go off. Likewise, if I try to lock/unlock the doors. Also, if I try to start it when it's in it's 'not starting' mode the headlights come on. Turn the key to start the engine and the headlights come on. And they don't go off after I cease attempting to start the engine.

So when it won't start the whole system seems to short out whenever I try to use any interior power accessories. And the headlights come on when I turn the key. When it will start everything seems to function just fine. However if I screw with the power seat or doors long enough it seems to create a short or something and it goes to the 'not starting' mode.

Also - not sure if this has anything to do with it or not - but there was an after market security system installed that the previous owners had disabled by disconnecting the battery connection. Originally I thought that perhaps this was the issue, but I disconnected the unit and nothing seems to have changed. There didn't appear to be any wires that needed to be re-wired to restore it to original condition but then I didn't tear the whole dash out. Maybe there's something else that needs to be done...???

I've done a bit of wrench turning over the years and usually I can figure stuff out, but electrical stuff obviously isn't my forte'.

This is the first time I've had stuff like this go on.

If anyone's got any ideas as to what it might be I'd appreciate the input.

Thanks!

[Mickey#1]

Power windows, door locks & fuel pump share a common ground at the driver's side ground bus. Pull the metal bar from the connector & clean the metal bar and female terminals inside the connector. Apply some dielectric grease to help prevent future corrosion. Here's a link to an article that has some pics showing the location of the ground bus. BTW - it's the connector where all the black wires meet. Let us know what you find.
http://www.bonnevilleclub.com/forum/...=article&k=102

[CentralOR]

Mickey#1,

Thanks for the info. Sure enough the driver side buss had an obvious short. It actually had shorted out enough to melt the plastic on the buss bar. I couldn't find a spare at the parts store but I have another Bonneville that isn't running at the moment because the a/c clutch is going out so I stole one from it.

Everything seems to be working just fine now!

Thanks again for the info!

[Mickey#1]

Great to hear that you got it going!