Powertrain, generic (extended)

P2E7D A/C Compressor Control Module Internal Temperature Sensor B Performance

Check engine lightOn
EmissionsNot relevant
Drive cycleRequired
Limp modeNo

P2E7D is the plausibility check for internal temperature sensor B of the electric A/C compressor controller: the reading is electrically in range yet conflicts with other temperatures. The test runs after a long rest, when all sensors should read alike. No manufacturer documents P2E7D. GM applies the method to its IGBT sensor (P0D76): the 2011 Volt tolerates 11 °C difference from ambient air and 7 °C from the CPU sensor after 21,600 s off, the 2019 tables 22 °C after 7,200 s in 8 of 10 s, Type B. Mitsubishi's Outlander PHEV compares two temperatures inside its front drive unit after a 3,600 s soak and fails at 18 °C; a Nissan patent judges an inverter switch sensor against coolant temperature. Drift, a still-warm compressor or a faulty reference can trigger it.

Likely causes

Sensor B drifted or poorly coupled to its measuring point
Comparison value wrong, e.g. outside air or second internal sensor faulty
Compressor still warm from recent use or preconditioning when the test ran

Symptoms

  • Usually no noticeable effect at first; fault stored after a cold start
  • Compressor may derate early or shut off on a wrong temperature
  • MIL on some vehicles after two drive cycles

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€50–2,500
Time0.5–5 h

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

Parts involved

ac compressor cm internal temp sensor bac compressor module

Related codes

P2E7CP2E7EP2E7FP0D71P0D76

References: gsi.ext.gm.com, gsi.ext.gm.com, mitsubishitechinfo.com, image-ppubs.uspto.gov.