Hi, I havent posted on here before so bare with me...

I did a quick search of some of the threads and didt notice any problems quite like mine, so here it goes...

I have a 90' GXL and for some reason the ADD COOLANT light + buzzer keep going off. The coolant level is fine, and the system has been bled. The oil level is also fine. The fuses are all in working order, and the only wiring that has been recently modified is the stereo, and it all checked out according to the wiring diagram that I have. The cars temp is right where it is suppossed to be, and I'm really at a total loss as to what the problem could be. Any insight would be helpful, as that the buzzer is insanely loud, as I'm sure you all know.

Thanks a lot guys.

 

You probably still have air bubbles that need to be bled out. However, if this is not the case, you probably need to replace the sensor.

 

Make sure the wiring is OK. The wiring on my old sensor was a bit frayed and one day after add coolant light buzzer kept going off (even though i bled it correctly etc) I decided to take it out and give it a once over. The cable snapped with me barely touching it.

You can always get another cheap one at the junkyard. I have one from another generation (s5 in my s4) so i'm assuming year isn't as important as model. Just make sure the wiring isn't frayed.

Other than that, go out first thing in the morning while the engine is cold and turn on the car without turning it over (radio works etc) and unscrew the sensor. Make sure you undo it from the harness. I'm just going to assume you're not too familiar with where it is, but it's on top of the radiator and it has a wire running to it. Take it out and touch it to some metal. If the buzzer stops the coolant really is too low. If it doesn't it means the sensor is bad, or something else is bad.

 

Yea mine does that too lol. My voltage regulator is bad, and for some odd reason, when I'm idiling and only putting out the 12V's needed to run the car, my add coolant light goes on. Start driving, and it's gone.


These cars are funny.