2000 Deville DHS Check Coolant Level message

PhilV · #1 (**permalink**) 10-08-09, 12:23 PM

Right after I had the coolant drained and replaced I began getting the 'Check Coolant Level' message right after start-up every time. I topped off with additional coolant with no change to the message. Seems like a possible bad sensor? I have 128k miles on the old buggy, but running well otherwise. The temp goes to and stays steady on 12 o'clock on the gage. Would replacing the sensor be the best move - or is there a way to disable the sensor by shorting the wires as I seen mentioned on other models. Also, is there an overflow tank - and where is it? I haven't had any luck locating one.

Thanks in advance,
PhilV

**Ranger** · #2 (**permalink**) 10-08-09, 01:08 PM

No "overflow" tank, only the surge tank. Can't change the sensor. You'll have to change the tank. I think you can unplug the sensor from below the tank and connect the wires, but of coarse you'll loose the early warning.

DevilleDeeman · #3 (**permalink**) 10-08-09, 01:23 PM

check the sensor at the bottom of the surge tank, the connection can get dirty...thats what happened to my '03 once. If the connection is ok, do what Ranger said replace the tank. Did you try clearing the code? Does it keep coming back?

CarCzar313 · #4 (**permalink**) 10-08-09, 02:34 PM

same thing happened to my 01 DTS after a flush/fill. Tank was full. Ran and cleared codes and it never came back. Temp gage reads high noon also.

submariner409 · #5 (**permalink**) 10-08-09, 03:00 PM

Maintain that surge tank at half full, cold. No higher.

The surge tank is the modern equivalent of the airspace in the top tank of an old downflow radiator: you must provide room for coolant expansion and contraction. No space and expanding coolant blows out of the cap pressure relief.

PhilV · #6 (**permalink**) 10-08-09, 04:56 PM

I've been clearing the code with the Info Reset button on the dash daily. I guess I should clear them with the code reader? I'll have a look at the connector on the bottom too, and recheck the fill level.

Thanks so far...

**Ranger** · #7 (**permalink**) 10-08-09, 05:47 PM

Quote:

Originally Posted by PhilV

I've been clearing the code with the Info Reset button on the dash daily. I guess I should clear them with the code reader? I'll have a look at the connector on the bottom too, and recheck the fill level.

Thanks so far...

No need for a code reader if you are clearing them correctly via the DIC.

submariner409 · #8 (**permalink**) 10-08-09, 06:54 PM

Sounds like he's turning off a DIC message with INFO RESET. Maybe hasn't read the sticky ^^^ "How to pull codes" because he also refers to an aftermarket code scanner.

It's already all built into the car...............

JimD · #9 (**permalink**) 10-08-09, 08:01 PM

Quote:

Originally Posted by PhilV

I've been clearing the code with the Info Reset button on the dash daily. I guess I should clear them with the code reader? I'll have a look at the connector on the bottom too, and recheck the fill level.

Thanks so far...

I think this issue has been unnecessarily complicated by a terminology problem.

Your CHECK COOLANT LEVEL is only a "message". It's information only and comparable to the ICE POSSIBLE message you might see. There are no "codes" associated with these "messages".

submariner409 · #10 (**permalink**) 10-08-09, 08:25 PM

You're so darn practical.....

arifleman · #11 (**permalink**) 10-30-09, 06:13 PM

I had a similar situation when changing coolant - recurring check coolant code, even though it was filled right to midlevel mark when cold. I stuck a long screwdriver shaft in the recovery bottle and tried to jiggle the sensor in the bottom of the tank. I also rapped the outside of the tank, where the sensor sits, with the handle of that screwdriver. One of those techniques worked. YMMV. Good luck all.

Mark C · #12 (**permalink**) 10-30-09, 08:10 PM

Happened to my Seville when I drained and replaced the antifreeze recently. I think when the coolant sealing tabs disolve some of it collects in bottom of the cylinder that the float switch in the surge tank travels up and down in and when you drain the system the float gets stuck in the gunk at the bottom of the shaft. After a couple of days and a few taps on the side of the tank, the float got freed up and everything is fine.

Marco · #13 (**permalink**) 11-14-09, 06:24 AM

Just received my new coolant recovery tank for my 2000 Deville from rockauto.

I'm replacing mine due to the plastic nipple developing a hairline crack/leak where the hose clamps onto the tank.

Figured I'd flush the system while I'm at it and refill with dexcool 50/50 by prestone.

Any danger in doing that? or do I need to buy the ac delco brand?

Also, what about the tablets? Is that still recommended for the 2000 base model?

submariner409 · #14 (**permalink**) 11-14-09, 10:36 AM

Prestone's DEX-COOL is perfectly OK. Don't get crazy with extended flushing or chemicals. Just drain as much as you can (2 - 3 quarts will remain in the block as there are no block drains) and refill with a proper mix of DEX-COOL and distilled water (supermarket). GM has pretty much discontinued the use of the Bar's tablets (or the powder, G12BP), so if you had no leaks before you started, there's no reason to use them now. IF you run clear water through the system and then drain it, mix your coolant at about 60/40 coolant to distilled water to account for the water still in the block and elsewhere.

caddi2323 · #15 (**permalink**) 11-15-09, 03:28 PM

I have the same message on my 2000 DTS. I have no idea how you go about using a long screw driver to push the floating sensor down and up because a little after the spout where you pour the coolant in, there is a screen type filter so you can't push a long screw driver down.

Do you stick the screw driver in side ways to get to the side of the reservoir?

Where is the sensor plug?

Is this method possible with my model here are a few pictures?