I had the low coolant warning light come on and added dexcool on my 1996 Z28SS. Now the light won’t go out. I thought it was air bubbles in the cooling system so I drove the front up ramps to get the radiator higher than the engine. I turned the heater on, then opened the two bleed valves until the dexcool was flowing. The low coolant light is still on!

The fluid was low when the light came on and it seems unlikely it would go faulty just after lighting. Do you have to get the front super high to get the air out the bleed valves? Any help appreciated!

 

The low coolant light has a “latching relay” in the circuit. That keeps the low coolant light on for an extended period of time so you don’t overlook it. In 96 they incorporated the latching relay in the body control module (BCM). Possibly a problem with the BCM, which is prone to deterioration of the printed circuit boards. Could also be a faulty coolant level switch, which corrodes due to coolant intrusion in the printed circuit board.

Unplug the low coolant sensor. If the light goes out, most likely a sensor problem. If the light doesn’t go out, most likely a BCM problem.

 

Thanks! I’ll test it out.

 

Unplug it and the light should go out. I got tired of replacing it for no reason on my 98TA and unplugged it. The same bad designed sensor is on all Gen 4 Firebirds.

 

Appreciate the advice, thanks!

 

4th Gen LT1 F-body Tech Articles

 

I cut open two of my failed sensors after they failed. Both were contaminated with the coolant (orange Dexcool). Bad sensor design.

 

Thanks for the link! A lot of good information.


Coolant time after time. Sounds like a waste to try to replace. Thanks!

 

I replaced mine when i had this issue and it never came back. Happened when the car was like 22 years old and i only had to replace it once. I would definitely replace it, the part was really cheap and it was easy to do so why not? Definitely a light i would want to function properly.

 

The original coolant level switch in my Formula was 27+ years old when I sold the car, still working, never replaced. It was relocated from the stock radiator to the Griffin aluminum radiator in 2000.

 

Naturally I’d like it to be perfect. Thanks for letting me know!

 

Wow, maybe it is worth trying to change the sensor, at least once. It does seem strange it would go out and the radiator actually be slightly low. Still no one’s talking air in the system, and I can’t find any, so I guess that’s not the thing.

Thanks for all the information and advice!

 

We're assuming you are capable of ensuring the radiator is actually full.

 

Yes I check the coolant, oil, brake fluid, power steering fluid,…. I also watch the oil pressure, coolant temp and battery charge as I drive.