View Full Version : check coolant light on???

12-18-07, 09:53 AM

changed coolant in 2001 deville/dhs 2 months ago, check coolant reminder keeps coming on every time I start car, but coolant level is fine.
Did not have this issue prior to changing coolant, any way to fix or find out what the problem is?

12-18-07, 12:07 PM
Define "coolant level is fine". It should be at least at the half mark. If it is half or better, then most likely you have a bad sensor in the tank. It is not serviceable. You have to replace the tank.

12-18-07, 02:10 PM
The coolant level is much higher than the half mark. (have topped off coolant level several times thinking level was low but never has been low)

If sensor failed and if I don't replace tank soon any problems as long as I keep checking coolant level manually?

12-18-07, 04:21 PM
The only problem will be the annoying message and the lack of a REAL warning.

12-21-07, 01:46 PM
just got transmission replaced, and got the car back runs well... the check coolant reminder is gone!!???
I don't know how that happened although I'm happy about it the message was annoying

12-28-07, 09:31 PM
Ajaved, my Deville has had the Check Coolant message on startup for about 100K miles. I check the rad every couple of weeks, it's never lost a drop. Since, as Ranger noted, you need to replace the overflow tank to get a new sensor, I have never bothered. If yours is NOT giving you the message now, it's possible that during the trans replacement, a wire got jiggled just enough to make it work again. I use the finger stick method - stick a finger in the (cool) overflow tank, note the level. If your finger comes up dry one time.....

01-04-08, 02:41 PM
Thought I would join on this one. I have the Check Coolant Level on every time I start my 2000 DTS. The system was serviced at the Dealer and I check and the coolant is at the proper level. I replaced the overflow tank with a new one from Dealer, refilled the coolant to the proper level, and STILL get the Check Coolant Level. Further check reveals the coolant is at the correct level.
Any idea why I still get the Check Coolant Level?

01-04-08, 06:53 PM
Must be a wiring issue I would guess. Not much else left, I don't think.

01-21-08, 10:27 AM
Thanks. I agree, not much left. I will take it in. The dealer here charges $350 minimum for a electrical diagnosis. I also have Steering Rate Sensor Malfunction (B1009), Check Security (B2734) on.

Do you know of a way to just disable the Check Coolant Level sensor? I am old enough to remember how to keep an eye on it anyway!!!!!
Thanks again.

01-21-08, 10:47 AM
....Do you know of a way to just disable the Check Coolant Level sensor? I am old enough to remember how to keep an eye on it anyway!!!!!
Remove the wire harness from the tank. Jumper the two pins in the chassis harness connector.

01-21-08, 06:40 PM
Easy enough. Thanks Jim. Brian

03-21-08, 01:48 PM
I am going to replace the coolant overflow/surge tank on my 2003 Deville. Two parts show up for the tank- one with a quick connector and one without the quick connector on the tank. The difference in price is about $12.00. Please adise the difference in parts. Which is best for this do-it-yourself tank replacement.
I am tired of that "Check coolant" light everytime I start the car.