exhaust gas temp 3 fault??

My guess is a faulty sendor, but the guys in the know will likely need more info, like engine make and model and year.

 

This will be the DPF outlet temp sensor/circuit. A lot of the harnesses are getting corrosion on the pins inside the connector body under the truck. The harnesses are about the same, but routed differently based on what truck you have. Some trucks have more than one connector. The harness starts at the DPF and runs up to the engine.

 

I get the Engine Warning light come on, then do a Diagnostic run, and get a similar message as yours "Sensor 3 reports excessive exhaust gas temps"

I usually run it that way to the next rest area, turn the truck off for 5 mins, restart and within 20 mins or so it usually comes back on again. Stop again at next rest area, shut down for 5 mins, and I'm usually good for another three months. I think Heavyd is right - they corrode and sent off flase readings, .... PITA.
Had the sensor changed twice, doesn't seem to make much difference

 

I'm getting the same thing 09 w900 with 525 six. Is it anything to worry about or just keep driving?

 

I think it will prevent the unit from doing a regen. If it won't do a regen you need to have this fixed because the DPF will only get plugged to the point where a tow truck has to be called.

 

My t660 is doing the same thing.... Did anyone find a fix?

 

Temp sensor or circuit fault.

 

How do you know for sure its just the sensor and not that it really is to hot?