OBD Guide

P1785

Transmission System First or Second Gear Fault Conditions

Severity
🔴 High
Can you drive?
Do not drive — repair immediately
Approx. repair cost
$33–167 (est.)

Symptoms

  • Problems shifting into first or second gear
  • The car jerks when changing gears
  • The gearbox goes into emergency mode
  • Increased engine speed when switching
  • Check Engine light comes on

Causes

  • Shift solenoids malfunction
  • Low or contaminated transmission fluid
  • Problems with the gearbox valve body
  • Friction disc wear
  • Malfunction of shaft speed sensors

How to Fix

  1. Check the level and condition of the transmission fluid
  2. Diagnose the operation of switching solenoids
  3. Check electrical connections and wiring
  4. Scan the transmission for additional errors
  5. If necessary, replace faulty gearbox components

Related codes

Error P1785 by Vehicle Brand