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Can someone with access to Ford service info do me a solid and look up DEF heater "C"?
A shop replaced the tank heater/sending unit which was not a fix. The heater that was removed checks good at 2.0 ohms with a multimeter. I'm wondering if heater "C" is for the pump heater. Searching the interweb hasn't produced any answers.
that is a "reductant heater C control circuit performance code" they/you need to test the relay for that circuit, pcm to relay wires and wiring to/from relay to the reductant heater including powers and grounds of heater at heater and ground point.
First thing , sorry I'm just seeing this 2 weeks after you posted it. I try to check out the diesel questions more regularly. There is a 25 amp fuse in the battery junction box. It should be fuse # 27. You need to check for B+ KOEO while commanding the heater with a scan tool at pin 16 (should be white and orange wire) at the glow plug control module. That input is controlled by the reductant heater relay which is powered by fuse 27 in the battery junction box. If the fuse is good but you still cannot command power you will have to do some regular relay checks at the reductant heater relay
