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2018 HONDA ACCORD
1.5L I4 Turbo•FWD•CVT•gas•turbo
6 active safety recalls on this vehicle — view recalls
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Repairs402Labor502Torque3379Fluid7DTC1924Battery1Maintenance0Recalls6
P0886high severityPowertrain

TCM Power Relay Control Circuit Low

on 2018 Honda Accord 1.5L I4 Turbo · FWD

What this code means

The TCM power relay control circuit voltage is too low. This suggests a short to ground or wiring fault in the relay control line.

Symptoms

  • Transmission stays in limp mode
  • Warning light illuminated
  • Delayed or no engagement

Common causes

  • Short to ground in control wiring
  • Faulty TCM power relay
  • Corroded connectors
  • Faulty transmission control module

Diagnostic steps

  1. Check control circuit for short to ground
  2. Test the power relay
  3. Inspect wiring and connectors
  4. Repair shorted wiring or replace relay
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