A few weeks ago the air conditioner drive belt broke when the compressor locked up. The compressor was replaced, along with the belt. After the belt broke, but before compressor was changed, other things began to happen. The dashlights blink, fuel gage goes to empty and then shows you have gas, speedometer goes 0 to whatever number (whether vehicle moving or not), low fuel light blinks, abs comes on, brake light comes on, check engine light, airbag light. These happen sometimes by themselves or all together. There aren't any lights on the gear shift, the anti-theft light stays on continuously, and the remote doesn't unlock the doors. The mechanic has changed out the body sensor module. The lights still appear. It will appear after the car has sat for a while. As of right now, we haven't been given anything except it might be. The mights are way too expensive and then it might not fix the problem.
You have multiple computers involved with all of these symptoms, and computers are very sensitive to system voltage. I'd start by testing the charging system. With the engine off, the battery voltage should be 12.6 volts. If it's closer to 12.0 volts, the battery is good but discharged. If it's around 11.0 volts or less, suspect a shorted cell and the battery must be replaced.
With the engine running, the battery voltage must be between 13.75 and 14.75 volts. If it is low, we'll need to measure the voltages on the two small wires on the back of the alternator to diagnose the problem. Those readings must be taken with the engine running.