Hi I have an 05 ext with 207K, the coolant sensor gauge worked when I first bought it a couple years ago, then sometimes it would not work and the needle would sit at the left at zero. Now it has not worked at all for quite a while, just sets pegged to the left. Is this more likely to be the sensor or the gauge? Seems like when the sensor goes out the needle usually bounces around, it might have done this but I don't remember this.
Thanks for the reply, yeah it was sounding like the sensor from what I have read, I wonder if anyone has been able to replace the sensor without taking out the alternator.
If you change the sensor, change the thermostat too. Same area and probably needs it anyway. But before that, have someone do a gauge sweep with a scan tool. They can see if the sensor is sending a signal to pcm also.
Hth
If you also have a check engine light and a code for coolant being too cold, then I would clear the code and see if it's like mine and the gauge starts working each time. Good luck.
What you need to do is not just start changing parts. Get a scan tool and see what it says the temp is. If it reads normal then it's the gauge, it it reads crazy then it's the sensor.
seems like it was normal temp but I will check it again when I get a chance that won't be until around xmas the vehicle is with my parents who live a ways from me
I can tell you that when it happened to me, I did the sensor/sender and I thought it was fixed. Then I did the cluster, for $200-ish, (plus $200+ deposit) and it also seemed fixed, for a day or two. But, for me, it always reads fine again after clearing the code, but it'll stop reading again 5 minutes or 5 days later. I suspect the ECM for mine, but I don't know what else "converts" the sender reading into the CAN BUS stuff. Good luck.
Rob in AZ
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Related Threads
?
?
?
?
?
Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum
1.3M posts
173.7K members
Since 2004
A forum community dedicated to Chevy Trailblazer and GMC Envoy owners and enthusiasts. Come join the discussion about performance, modifications, troubleshooting, towing capacity, maintenance, and more!