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P0885high severityPowertrain

TCM Power Relay Control Circuit/Open

on 2008 Dodge Viper 8.4L V10 · RWD

What this code means

The control circuit for the TCM power relay is open or not functioning. The TCM cannot properly command its power relay.

Symptoms

  • Transmission does not shift
  • Warning light on
  • No power to transmission control system

Common causes

  • Faulty TCM power relay
  • Open in relay control wiring
  • Corroded relay socket
  • Faulty transmission control module

Diagnostic steps

  1. Test the TCM power relay operation
  2. Check control circuit continuity
  3. Inspect relay socket and connectors
  4. Repair open wiring or replace relay

Other Powertrain codes on this vehicle

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