OBD Guide

P1858

Transmission Transfer Case Contact Plate 'D' Circuit Failure

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$17–89 (est.)

Symptoms

  • Check Engine light comes on
  • Problems with switching all-wheel drive modes
  • Unstable operation of the transfer case
  • Reduced controllability on difficult road conditions
  • Possible jerking when changing gears

Causes

  • Open or short circuit in contact plate 'D' circuit
  • Damage to transfer case contact plate
  • Problems with the transfer case wiring harness
  • Transfer case control unit malfunction
  • Corrosion of contacts or connectors

How to Fix

  1. Check continuity of contact plate 'D'
  2. Inspect the contact plate for damage
  3. Check the condition of the wiring harness and connectors
  4. Test the transfer case control unit
  5. If necessary, replace the contact plate or repair the wiring

Related codes

Error P1858 by Vehicle Brand