I have a 160c LC that the gauge in cab will not read correctly. I have replaced the two sensors on thermostat housing with no luck and also installed temp switch. I took the single wire from main temp sending unit and grounded to engine and gauge will peg out hot. On the temp sensor on bottom of housing I’m getting 5v there but jumping across pins does nothing on gauge either. I have not checked to see if I’m getting voltage to single wire sending unit yet. Temp switch works cause the machine is getting hot after couple hours running and gauge pegs out and alarm buzzer goes off. I have also checked to make sure main temp sending unit (single wire) is grounding to engine so it’s getting a good ground. Any ideas I figure wire is good since the gauge pegs out when taking single wire to ground gauge pegs hot? Could dash cluster gauge be bad even tho it moves when engine over heats or you ground that single wire? Thanks for any and all input
The temperature switch at the top rear of the head is for the temperature light. If it trips, the light will illuminate, and then at the same time send the gauge to maximum hot temp (the monitor controller controls this, not the sender directly). A short in the sensor or wiring can also cause this. if it is the sensor, then unplug it and see if the issue goes away. The single wire sender at the thermostat housing is for the gauge. Both of the above communicate directly with the monitor. The two wire sensor at the thermostat housing is for the ECU to monitor engine temperature and it does not affect the gauge or the indicator light, but it will light the check engine light in an overheat event. Is your machine in fact overheating? Confirmed with a temp gun?