OBD Guide

P1765

Transmission 12V Supply Relay Control Conditions

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$17–111 (est.)

Symptoms

  • Delayed gear shifting
  • The gearbox goes into emergency mode
  • Check engine light comes on
  • Malfunction of automatic transmission solenoids

Causes

  • Faulty automatic transmission power relay
  • Open or short circuit in the relay control circuit
  • Poor contact in connectors
  • Transmission control module (TCM) malfunction
  • Power or grounding problems

How to Fix

  1. Check the automatic transmission power relay and replace if necessary
  2. Check the relay control circuit for opens and shorts
  3. Inspect and clean all connectors in the circuit
  4. Check the power supply and grounding of the control unit
  5. If necessary, replace the transmission control unit

Related codes

Error P1765 by Vehicle Brand