Powertrain, generic · Hybrid propulsion

P0CA1 Drive Motor Control Module Requested MIL Illumination

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modeNo

P0CA1 is a request code, not a component fault: the drive motor control module has detected an emissions-relevant fault of its own and asks the engine control module to light the MIL, which stores P0CA1. Subaru documents this on the 2014 XV Crosstrek Hybrid in bulletin 07-82-14R: P0CA1 sits in the engine module and C1424 in the stability control module, both MIL requests comparable to P0700. They usually accompany the drive motor module codes P0CDD and P0A3F, which set when the 12 V auxiliary battery voltage drops; with those codes in history, reprogramming the drive motor module is the fix, and Subaru changed its logic in production from January 2014. If only P0CA1 and C1424 are present, diagnose per the service manual.

Likely causes

Emissions-relevant fault stored in the drive motor control module
Module software reacting to a low 12 V battery (Subaru 07-82-14R)
Weak or discharged 12 V auxiliary battery

Symptoms

  • Check-engine lamp, often with further warning lamps such as stability control
  • Hybrid drive behaving normally or with reduced electric assistance

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€0–600
Time0.3–2 h

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

Parts involved

drive motor control modulemodule communication bus

Related codes

P0A7BP0AC4P0700P0CDDP0A3F

References: static.nhtsa.gov, law.cornell.edu.