Cooling gauge and fan

NMCPHERSON

MEMBER
2001 CHEVROLET CAMARO
3.8L
V6
2WD
AUTOMATIC
150 MILES

My temperature gauge went from reading to not and the fans kicked on. I replaced the thermostat and coolant temp sensor. And nothing. You start the car and the fans are running on high automatically with the gauge not registering. I pulled the fan control fuse and the stayed on same when I pulled the fan fuse. I pulled relays one by one starting at the front and nothing changed until relay closest to the windshield car shut off. I swapped the relays and it was the same. Any ides.

Tuesday, November 20th, 2018 AT 1:57 PM

1 Reply

JACOBANDNICKOLAS

MECHANIC
110,068 POSTS

Hi and thanks for using 2CarPros.

It sounds like there is a short to power. Do me a favor, I attached a diagnostic flow chart for this symptom. Also, I attached a schematic for the cooling fan circuit (picture 2). There are three relays which control the fan speed. If you removed one relay at a time, it could have kept running. Next, I attached a diagnostic flow chart for the temperature gauge. It requires a live data scanner. See picture 3. Pictures 4 and 5 are of the power distribution box under the hood. It shows where the three relays are located and fuses.

Here is a link that shows how to test a relay:

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

You will need to use a test light for testing the relay. Here is a link that shows how to use one:

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester

Let me know if any of this helps.

Joe

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