John Deere 5100M Hydraulic Temp. Code

[levibaker1982]

Afternoon all,

I’m working on a John Deere 5100M that keeps throwing a code (Ccu 1638.00) for hydraulic fluid overheat. Unplugged sensor started tractor (cold) alarm stops, but light stays on and still throws code. Hooked new sensor into harness not installed in tractor, still throws code. Anyone had any instances with this?

 

[used red MN]

Haven’t worked on that tractor or really diagnosing codes on any tractor. Carrying the steps required over from automotive code work there is generally a troubleshooting tree diagram in the manual/software that goes along with a code to determine if the sensor is indeed the problem or the circuits/wiring is at fault. Seems to me that is where you need to go.