After i finished replacing the thermostat the other day i have noticed that non of my warning light on the dash will turn OFF when the engine is running - its in the state like when you have the ignition on before you start the engine, i also noticed that my elect sliding door has stopped working as well. I have checked all fuses and disconnected the battery for a bit to try and reset ecu but still same? I think has something to do with the plug on the back of the alternator because i had it unpluged while replacing thermostat. This plug has something to do with the warning light circuit because if i unplug it the warning lights go out. I looked at the plug up close and all three pins are ok not broken so i guess my QUESTION is what are those three wires doing? Sliding door relay supply, battery light and the rest of the warning lights?? could there be a switching diode in the alternator thats failed? Im a domstic electrican not an auto sparks unfortunately!