2007 Corvette temp sensor issues...XXX

[Kingsize]

I have been trying to get the Coolant Level Low and Check Coolant Level on the DIC to stop reporting. It also effects the Analog and digital gauge, as they are bouncing up and down from 25 degrees to 169. I have previously disabled P0128 and set to No MIL due to the ECM throwing XXX on the DIC and cutting the air conditioning off. I researched what I could find, and seen that the computer does not like the temp either not coming up fast enough, or not getting as hot as it would like. What else need to be turned off for the gauges to work correctly and the DIC to not report temp issues when there are none. I have a 440LS7 w/an electric WP and 160 thermostat. No temperature issues during the summer, but this thing drives me nuts during the winter. Thanks for any help that can be provided.

Also, I pasted a copy of my tune so you can see what all is what. If you see something out of whack, feel free to let me know. Still somewhat of a newb at this.

[Sherminator]

Did you look into a bad sensor being the problem? Is is even hooked up? Bad wiring?

[Kingsize]

Yes... Sensor is new, wires checked, and yes it is hooked up. This only happens during the winter. During the summer it goes away and it only comes back next winter.

[JoeyJoeJoe]

IIRC. The C6 Vettes dont have a physical coolant level sensor. They use and agorithim to figure out if the car is low on coolant by how long it takes the coolant to warm up after start up. I have seen this a lot with lower than stock temp t-stats. I dont think we have the option to change anything that would make it act correctly.

[Sherminator]

Yes mine had a 160 and with the cooler fall/spring temps it took literally half way to work to warm up to normal stabilized temp. This year I'm doing a stock one and seeing what happens(I have a Dewitts rad and external oil cooler).

[Kingsize]

It can be corrected from the research I have done. A few have had it tuned out a local speed shops. My only issue is, I have yet to find a definitive answer on exactly what to do.

LOL

[JoeyJoeJoe]

I just reread your first post. Bouncing around that much is not normal. How fast does it bounce? Are you talking about the gauge on the dash(analog) and the one in the DIC(digital) or do you have aftermarket ones? Are you low on coolant, or is coolant not getting to the sender? They act really weird when they are getting splashed with hot coolant rather than being submerged in it. Is your t-stat stuck open?
As far as tuning out the Check coolant level and Coolant low DIC, do you know if whoever accomplished it was using HPT?

[JoeyJoeJoe]

Found this on another forum:

"The 2005 Chevrolet Corvette utilizes an algorithm-based low coolant level system which eliminates the need for the coolant level sensor previously positioned inside the surge tank (fig. 12).

The algorithm (a mathematical calculation) measures the difference in engine coolant temperature readings over time as a function of engine speed, to determine if the cooling system has a low coolant condition. After vehicle start-up, the ECM sends an engine RPM and engine coolant message through the BCM to the HVAC control head. The HVAC control head uses engine coolant temperature and engine RPM to determine if an increase in coolant temperature is due to a low coolant level condition.

This system is capable of losing 2 full liters of coolant before triggering the Low Coolant warning message. Because the surge tank holds approximately 0.8 liters when filled to the proper level, it's possible that a Low Coolant warning message is not triggered, even though the surge tank is completely dry.

TIP: After filling a system that has triggered the Low Coolant indicator message, the ignition must be cycled to turn the Low Coolant indicator off.

Diagnostic Tips
In the event that the Low Coolant message is present and the coolant is not low, verify that the RPM and Coolant Data (GMLAN) sent to the BCM matches the RPM and Coolant Data (Class 2) sent to the HVAC control module. If the RPM and Coolant GMLAN and Class 2 Data do match, the HVAC Module software needs updated. If the RPM and Coolant GMLAN and Class 2 Data do not match, the ECM and BCM software need updated.

TIP: This assumes that there are no RPM or Coolant codes set and no other messages or symptoms are present."

I am guessing that we can not do anything with out access to the HVAC and/or BCM, but if I am wrong someone please let me know.

[Kingsize]

Coolant system is perfectly fine it has never overheated and has always run cool. Only time I ever have issues is during winter. It is completely a computer issue.

[Mike@G-Force]

Did you disable the Coolant thermostat code in the dtc section?

[Kingsize]

Did you disable the Coolant thermostat code in the dtc section?

Hey Mike, Thanks for coming in here. I heard you were one of the guys that knew how to disable this issue. I only disabled P0128 and set it to no MIL. That took care of the XXX and the AC off issue but the rest is still present like fluctuating temp on the analog and digital gauge as well as the DIC notifications. I also posted a copy of my tune file in my first post if you wouldn't mind looking at it.

[Mike@G-Force]

Hey Mike, Thanks for coming in here. I heard you were one of the guys that knew how to disable this issue. I only disabled P0128 and set it to no MIL. That took care of the XXX and the AC off issue but the rest is still present like fluctuating temp on the analog and digital gauge as well as the DIC notifications. I also posted a copy of my tune file in my first post if you wouldn't mind looking at it.

I will look at it at the shop monday.

Also try setting the 0128 to no error reported instead of no mil.

[Kingsize]

I will look at it at the shop monday.

Also try setting the 0128 to no error reported instead of no mil.

Looks like I was mistaken Mike, it was already set to no error reported instead of no mil.

[NICKY BOY]

seen this myself. turned out to be bad connection at sensor.

[Kingsize]

Bumping this to see if you have gotten a chance to look at the tune yet Mike. And as stated above, the sensor is new and all wires were checked and weather pack connector is in good condition. Again... This only happens during winter. It Never happens any other time. It has nothing to do with the sensor or the wires. It is a tune issue with the computer wanting the temp to come up faster and get hotter than what it will get when it is cold out.

[Tricked-Out-Toy]

Bumping this to see if you have gotten a chance to look at the tune yet Mike. And as stated above, the sensor is new and all wires were checked and weather pack connector is in good condition. Again... This only happens during winter. It Never happens any other time. It has nothing to do with the sensor or the wires. It is a tune issue with the computer wanting the temp to come up faster and get hotter than what it will get when it is cold out.

Did this ever get resolved? Im having the same issue on two c6z's. one will set the code after driving for a while with a 170deg tstat. the other sets the code immediately after sitting overnight. disconnecting/reconnecting the battery fixes both and they both start reporting temp as normal.

[C6GS]

I'm curious as well. I'm having sporadic XXX as well. High engine temp a/c off. However ECT reads fine over HpTuners.

[schpenxel]

Had the same.

P0116 set to no error reported fix it for me

[C6GS]

Thanks guys, fixed! 3 weeks with no A/C in Florida this time of year SUCKS! I appreciate it

[schpenxel]

What fixed it?