Temp gage pegged

[lylekh]

What would make my temp gauge. peg all the way clockwise even when car is off? I just put in new radiator and thermostat. Temp gauge worked fine before this.

 

[ulycyc]

Check the harness going to the coolant temp. sensor. Maybe you pulled on it and its grounding out when doing your work. It should have 3 wires

 

[lylekh]

Thanks. When I disconnect the temp sensor, the gauge doesn't do anything but the radiator fan come on. When I reconnect it, the fan goes off so I guess it and the computer are working. Gauge still pegged. I'm starting to think bad gauge. Maybe it got zapped when I reconnected the battery? Weird. Too much of a coincidence with me changing radiator and thermostat.

 

[ulycyc]

Get a strong magnet and wrap with a tissue so you don't scratch the glass.
With the engine cold, ignition on engine off place the magnet on the dash over the temp gauge.
Try and slowing twist the magnet both ways until the needle resets and goes to the cold mark.
Then turn off ignition. Start car and see if it works. It's a easy free fix and should work if it was caused by a spike during battery replacement.

 

[lylekh]

I read about the magnet trick yesterday. It didn't work with my magnet on a stick. Tried again today with a strong magnet (from an old hard drive) and that needle flipped around like crazy! All is well now. Guage works fine! Thanks for the replies!