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2021 TOYOTA C-HR
2.0L I4•FWD•CVT•gas•M20A-FKS
1 active safety recall on this vehicle — view recalls
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Repairs0Labor476Torque3059Fluid7DTC1942Battery1Maintenance0Recalls1
P0888high severityPowertrain

TCM Power Relay Sense Circuit High

on 2021 Toyota C-HR 2.0L I4 · FWD

What this code means

The transmission control module sees higher than expected voltage on the power relay sense circuit. This usually points to a stuck relay or a wiring fault.

Symptoms

  • Transmission warning light on
  • Shifting problems or limp mode
  • Relay may stay energized

Common causes

  • Stuck or shorted TCM power relay
  • Wiring short to voltage on sense circuit
  • Corroded relay connectors
  • Faulty transmission control module

Diagnostic steps

  1. Scan for related transmission codes
  2. Test TCM power relay operation
  3. Measure sense circuit voltage
  4. Inspect wiring for short to power
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