OBD Guide

C1209

ABS Rear Isolation Valve Circuit Short To Ground

C1209 is an OBD-II diagnostic trouble code meaning: ABS Rear Isolation Valve Circuit Short To Ground. Common causes: wiring harness damage, abs rear circuit isolation valve malfunction. Estimated repair cost: $56–167.

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$56–167 (est.)

Symptoms

  • ABS light is on
  • Reduced braking performance
  • ABS activation during normal braking

Causes

  • Wiring harness damage
  • ABS rear circuit isolation valve malfunction
  • Problems in the ABS control unit
  • Short circuit to ground

How to Fix

  1. Check wiring harness for damage
  2. Check the resistance of the ABS rear circuit isolation valve
  3. Check the ABS control unit for errors
  4. Replace faulty components

Related codes

FAQ

What does the C1209 code mean?

C1209 is an OBD-II diagnostic trouble code that indicates: ABS Rear Isolation Valve Circuit Short To Ground

What causes a C1209 error code?

The most common causes of C1209 include: Wiring harness damage; ABS rear circuit isolation valve malfunction; Problems in the ABS control unit; Short circuit to ground.

How do I fix a C1209 diagnostic trouble code?

To fix C1209: Check wiring harness for damage. Check the resistance of the ABS rear circuit isolation valve. Check the ABS control unit for errors. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with C1209?

Limited driving only, diagnose soon

How much does it cost to fix C1209?

The estimated repair cost for C1209 is $56–167. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat