ABS and brakes

C0081 — Traction Control Disabled by PCM Request

Severity: medium Drive with care, to a shop

What C0081 means

The powertrain control module (PCM) sent a request to the brake control module (EBCM) to disable traction control. Normally TCS brakes a spinning wheel and asks the engine to cut torque. If the PCM has its own fault or communication between modules breaks down, it disables TCS so the systems don't conflict.

Symptoms

  • TCS off or traction control light on
  • Check Engine light on
  • Reduced engine power or limp mode
  • Wheelspin on slippery surfaces
  • Possible ABS or stability control warning

Possible causes

  1. An engine fault with its own stored PCM code
  2. PCM-to-EBCM communication problem (data bus)
  3. Damaged wiring or corroded connectors
  4. Faulty accelerator pedal or throttle position sensor
  5. Low battery voltage or poor ground
  6. PCM or EBCM software glitch
  7. Intentional limp mode commanded by the PCM

How to diagnose

  1. Scan all modules for codes, especially the PCM, and note freeze frame data
  2. Diagnose and fix any engine codes first: misfires, throttle, pedal sensor
  3. Test battery voltage and charging output
  4. Inspect PCM and EBCM connectors, harnesses and grounds
  5. Check the data bus lines for opens or shorts
  6. Watch live wheel speed and pedal position data
  7. Check for PCM or EBCM software updates
  8. Clear the code and road test to see if it returns

Common fixes

  • Repair the engine fault that triggered the request
  • Fix damaged data bus wiring or connectors
  • Replace a faulty pedal sensor or throttle body
  • Replace the battery or restore a good ground
  • Update or reflash the PCM or EBCM
  • Replace a failed control module only after testing confirms it

Questions and answers

What does C0081 mean?

The PCM asked the traction control system to turn off. It is usually caused by another engine fault or a communication problem between modules.

Can I drive with code C0081?

Yes, carefully. Traction control won't help you and engine power may be limited, so don't put off diagnosis.

How do I clear C0081?

Find and fix the cause first, mainly any PCM codes. Simply erasing the code will likely let it come back.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.