Powertrain, generic

P0EC5 A/C Compressor Motor Speed Sensor Range/Performance

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

P0EC5 means the speed information of the electrically driven compressor motor is implausible: the motor does not turn at the speed the controller expects, or the reported value contradicts other data. Mazda uses the code on the 2024 to 2026 CX-90 PHEV and 2025 to 2026 CX-70 PHEV, describing P0EC5:00 in the PCM as an error signal coming from the compressor. Bulletin 07-002/26b lists it beside P0D6D, U0605 and P0AA6 when an overcurrent shorts the compressor internally and the high-voltage A/C fuse blows; the A/C then stops cooling. GM's 2011 Volt ran a similar test as P1F0A, Type B: fault if the spinning motor stays below 1800 rpm for 20 seconds.

Likely causes

Internal short in the electric compressor after overcurrent (Mazda PHEV)
Blown high-voltage A/C fuse cutting compressor power
Mechanical drag or lack of oil keeping the motor below target speed

Symptoms

  • A/C does not cool
  • Accompanying compressor voltage, communication or insulation codes

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€150–3,000
Time1–6 h

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

Parts involved

ac compressor motorac compressor module

Related codes

P0D6DP0D6FP0EAEP26FDU0605P0AA6

References: static.nhtsa.gov, gsi.ext.gm.com, law.cornell.edu.