OBD Guide

P1826

Internal Mode Switch Circuit 'C' High

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$28–89 (est.)

Symptoms

  • Incorrect detection of gear selector position
  • The gearbox only works in one gear
  • Transmission fault indicator flashes
  • The car does not move in the mode selected by the shift lever
  • Lack of response to mode switching

Causes

  • Short circuit to power supply positive
  • Broken or damaged wiring
  • Malfunction of the internal mode switch
  • Connector problems or contact corrosion
  • Transmission control unit malfunction

How to Fix

  1. Check the switch circuit wiring for damage.
  2. Check the resistance of the mode switch
  3. Inspect connectors and contacts for corrosion
  4. Check for short circuit to positive
  5. If necessary, replace the faulty mode switch

Related codes

Error P1826 by Vehicle Brand