OBD Guide

P1788

3-2 Timing/Coast Clutch Solenoid Circuit Open Conditions

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$17–56 (est.)

Symptoms

  • Gear shifting problems
  • The gearbox goes into emergency mode
  • Check Engine light comes on
  • Unstable engine operation when shifting gears
  • Loss of power during acceleration

Causes

  • Open circuit in solenoid circuit
  • Clutch solenoid malfunction
  • Wiring harness damage
  • Oxidation or damage to connectors
  • Malfunction of the transmission control unit (rare)

How to Fix

  1. Check the continuity of the solenoid circuit
  2. Check solenoid resistance
  3. Inspect and clean connectors
  4. Replace solenoid if necessary
  5. Check the operation of the gearbox control unit

Related codes

Error P1788 by Vehicle Brand