OK, I'm driving my '94 Bonneville and the SES light comes on and then, when I put on the brakes, it chimes and shows the 3rd brake light has failed... Then it runs rough and idles poorly. I took it to O'Reilly and they can't get their code reader to even read anything, much less pull a code. I disconnect the battery for a few seconds and restart the car and the SES light is off, the 3rd brake light failure is cleared, and the car runs just fine. This has happened more than once--same symptoms, same results from disconnecting the battery. It'* not a closed-loop/open-loop issue as the car runs fine warmed up or cold (i.e., in open loop and closed loop mode) for a long time before throwing the code and chiming the chime. I know I've got to find somebody (not the dealer! $100+ minimum to hook it up) to pull the code when it shows up, but I'm hoping this combination of events will chime in someone'* memory and they'll say "Oh yeah, I had that happen and it was the -----." Anybody?
TIA
Keith

The scanners at auto parts stores will not work with your OBD1.5 car. You have an OBD2 connector with a OBD1 brain. You need to get your own scanner to read that car: http://www.bonnevilleclub.com/forum/...ic.php?t=40209

Have you check the actual bulb in your 3rd brake light to see if its out?

I did check the bulb, and the first time it wasn't out. When the code cleared the fault cleared. The third time, however, the bulb WAS out. Weird. I'm beginning to think the two things (code and bulb) aren't related.

They're not related unless you have a very weak alternator.

Boy I hope not. I've got enough problems with this car (although, actually, less than I expected).