Powertrain, generic · Hybrid propulsion

P0C1E Electric/Auxiliary Transmission Fluid Pump Control Module Internal Temperature Sensor Circuit Low

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modePossible

P0C1E reports that the signal voltage of the module's internal temperature sensor is below its valid range. With the usual NTC thermistor, low voltage corresponds to a very high temperature, so a short to ground looks like an overheated board. No manufacturer documents this exact code publicly. GM shows the scale on the 2016 ELR pump controller with its own code P1E35, labelled circuit low: a reading above 130 °C, near 0 V, for 250 of 350 samples at 10.4 ms sets a Type B fault, MIL after two trips. The Honda CVT pump patent uses this board value to cut the pump relay, so a shorted sensor can stop the pump although nothing is hot. P0C1F is the high side, P0C1B a genuine overtemperature.

Likely causes

Board temperature sensor or its signal path shorted to ground inside the module
Measuring circuit of the pump control module faulty
Fluid or moisture on the module board

Symptoms

  • Pump switched off as if overheated, auto-stop unavailable
  • MIL after two drive cycles

Repair estimate

DifficultyHardWorkshop job
Parts and labour€300–1,800
Time1–4 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

aux trans pump control module

Related codes

P0C1BP0C1CP0C1DP0C1F

References: law.cornell.edu, gsi.ext.gm.com, patents.google.com.