'97 Bonneville electrical systems off & car stops

[munier2001]

Last week I was driving my '97 Bonneville when the radio went off and when I looked down the clock was also off. I realized the car was no longer running. Thankfully I rolled to a stop at a stop sign. When I put the car in park it would not turnover at all. No sounds of power in the car and no clicking from the starter. My power windows would not work. I was pushed to the side of the road. I was still sitting in the drivers seat with the keys in the ignition turned slightly. While sitting the power came back on and I was able to start the car without any problems.

We had the battery that was in the car tested and it tested okay except for being slightly low at one point. So, we went ahead and replaced the battery to eliminate that possbility.

However, now my gages are not reading correctly when I start the car. The gas gage will read full and fluctuate quickly up and down. After the car has been running for a few minutes the gas tank reads accurately.

Any ideas? Could it be the alternator? It still has the original alternator. I'm hoping it isn't the computer.

[randman1]

Geeeze, that's a head scratcher. After the car stalled and the radio & windows were not working, did anything work? Dome lights, cig plug for the cell phone, anything???

If the alternator is at fault, the car would be draining the battery to the point to where the ignition module can no longer fire the plugs and yes, the car would stall. I don't think however that you would be able to start it up as easily as you described afterwards.

I was still sitting in the drivers seat with the keys in the ignition turned slightly. While sitting the power came back on and I was able to start the car without any problems.

Was the switch in the "on" position? I'm almost tempted to say a faulty ignition switch connection. The fact that the radio display turned off indicates that there was no voltage present to the accessory feed. The windows are on a different circuit as is the engine stuff (alt, PCM, ign module, etc). On my diagram (for a 93) it's showing two red wires coming into the ignition switch. One runs the heater circuit (powered only when the key is in the run position) and the other runs the accessory, ignition and crank circuits. This second one is rather suspicious.

I would see if you can get a hold of a wiring diagram specific to your year because there might be slight differences from the 1993. This also may not be the solution to your problem but it certainly is a good place to start as it make sense according to your description.

Let us know how you made out.