ECT sensor voltage

Hello,

The Power-train Control Module[PCM]/Engine Control Unit[ECU] uses resistance readings to measure the temperature of the coolant, not voltage. In the diagrams down below I have included the description of how the Engine Coolant Temperature sensor[ECT] works and expected resistance values at varying coolant temperatures for your vehicle. Please go through these guides and get back to us with what you find out.

Thanks,
Alex
2CarPros

I’ve been using ALDL droid and I’m getting a coolant temp sensor Alarm trigger but the temperature reading is somewhat correct. I am not getting any codes on ECM either. Every now and then I have an idling issue though and today while driving my truck wouldn’t shift into overdrive temperature gauge stopped reading oil pressure gauge stopped reading and also my ALDL cable stopped reading and communicating then everything started working again.

I got a resistance reading of 960s with the engine cold and multi-meter set to 200 ohms I checked it by putting hot on yellow wire and ground on black wire with a wire piercing probe and key was off.

Hello again,

If the engine and the coolant was cold, then that reading is too low. I would recommend taking that sensor back and exchanging it for a different one. Also, please make sure that you are getting the Engine Coolant Temperature Sensor and not the switch. There are two ECT's for your vehicle. The sensor is what the PCM uses and there is also a switch, that looks just like the sensor but is used by the coolant temperature gauge. They have different resistance values. In the diagrams down below I have included a diagram of the locations of both the ECT sensor and switch for your vehicle as well as the Original Equipment Manufacturer[OEM] part numbers for both for your reference. Please get back to us with how everything turns out.

Thanks,
Alex
2CarPros