STOP Indicator and Water Temp Light Malfunction

[deshet]

My stop indicator light and Water Temp Light have come for no reason.
They come on and the engine is cold with full coolant.
I am hoping for a simple fix, bad ground or nicked cable.
Has any one else had this problem.
I still can't raise my cab so I don't have the full picture yet. (Hydro Pump Piston and Seal)

I just put 700 miles on the truck. It had 1300 miles on it. No issues during the entire trip. I did see the lights barely light for 2 seconds during one of the startups and go out.

Know they are full on regards of temps with no overheat issues at all.

Thanks

 

[Awesomeness]

It's hard to tell until you get the cab up. If I remember correctly, the switch for this is on the passenger side, at the top of the water pump or thermostat housing, right above the alternator. When working correctly, as the coolant temperature hits 230 degrees, this Normally Open (NO) switch closes, and turns on both the overheat and stop dash lights. It doesn't do anything else, and isn't connected to anything else (e.g. it can't shut down the engine, it's just a warning light).

You can see all this in the wiring diagrams in the manuals. Once you can lift the cab, you can test it with a multimeter to see if it is in fact completing a circuit when cold, which would indicate it is bad. I think they are $150 new.

 

[deshet]

Drove the truck last night and this morning and the light went off. I will see if it comes back. I believe that it most be a loose wire.

Thanks

 

[Awesomeness]

A loose wire could turn something off , but not on.

 

[Sweep]

If the temp sensor is by the thermostat, then what is the sensor on the hard coolant line that runs up and down in front of the block?

 

[Awesomeness]

If the temp sensor is by the thermostat, then what is the sensor on the hard coolant line that runs up and down in front of the block?

I don't recall. It was about a year ago that I was tracing all this out. If yours has a numbered metal crimp tag on it, you can look that number up in the TM's wiring diagrams.