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ECT sensor or gauge issue? Ahhh gremlins
I apologize in advance for the lengthy post but I wanted to try and make it as clear as possible.
I replaced my crapped out water pump. I could not remove the old ECT (Engine Cooling Temperature) sensor so I got a new one from O'riely's. Dealer was closed for two days and I needed to get back on the road. After finishing the job my temp gauge is dead.
I have taken several routs to root out the problem and I am kinda confused as to where the problem lies. I went to the dealer and the tech there removed the connector to the sensor at the pump and had me turn the key to the on position. Nothing happened. He responded by saying that the gauge was faulty, not the new sensor since removing the plug will make the gauge jump to the all hot position. I thanked him and resigned myself to getting an after market gauge rather than getting a new instrument cluster.
However, before I go any further I decided to take the dash apart and to see what, if any, voltage reading I am getting from the associated wires from the sensor to the gauge. My Chilton guide shows the red/white wire leaves the sensor and goes to the dash gauge and the pnk/org goes to ground (somewhere, though i cant trace it). I see that along its way it goes through a 42 way connector. when the truck is warm I get no voltage from the red/wht wire at the instrument cluster. It makes sense that if the gauge is faulty I should still get voltage (as I assume the sensor is basically a thermocouple) from that wire at the dash but I am not. This makes me feel like something came loose at the clip for the sensor or along the wires path to the dash.
I get no voltage from the sensor if I test it with my multimeter. I feel as though I should get something from it if the truck is warmed up. I have continuity from connector at sensor to wire in dash and ground. should I get a voltage reading from the sensor itself or should I be measuring resistance? If resistance, what is normal? I thought I would ask and see if anyone had anything that might help me figure it out. I am very nervous about driving around without a functioning temp indicator.
2001 7.3L F350, 175,*** miles