Transmission

P0891 — Clutch Solenoid Circuit Low

Severity: medium Drive with care, to a shop

What P0891 means

The transmission control module (TCM) monitors the voltage in the circuit of the solenoid that controls clutch engagement. If the voltage is lower than expected, for example from a short to ground or a failed solenoid winding, it sets P0891. The transmission often switches to a fail-safe mode as a result.

Symptoms

  • Check Engine or transmission warning light on
  • Clutch or transmission slipping
  • Harsh or jerky shifts
  • Limp mode or stuck in one gear
  • Difficulty pulling away from a stop
  • Poor acceleration

Possible causes

  1. Short in the clutch solenoid circuit
  2. Failed clutch solenoid
  3. Internal fault in the mechatronic unit
  4. Damaged wiring or corroded connectors
  5. Short to ground or to positive in the harness
  6. Faulty TCM power relay
  7. Failed transmission control module (TCM)

How to diagnose

  1. Scan all codes and freeze frame data and look for other transmission faults
  2. Check fluid level and condition where the design allows it
  3. Inspect the transmission harness and connector for chafing, oil and corrosion
  4. Check TCM power supply, fuses and relay
  5. Measure solenoid winding resistance and compare with the manufacturer spec
  6. Test the circuit wires for opens and shorts to ground or positive
  7. Command the solenoid with a scan tool and watch its response
  8. Only then suspect the mechatronic unit or the TCM

Common fixes

  • Repair damaged wiring or replace the connector
  • Replace the TCM power relay or fuse
  • Replace the clutch solenoid
  • Repair or replace the mechatronic unit
  • Replace or reprogram the TCM
  • Clear the code and run a transmission adaptation

Questions and answers

What does P0891 mean?

It means the clutch solenoid circuit signal is low. The transmission control module sees lower voltage than expected, often from a short or a failed solenoid.

Can I drive with P0891?

Only briefly and carefully, to a repair shop. Slipping can quickly damage the clutch and transmission, so do not put off diagnosis.

Will clearing P0891 fix it?

Clearing only turns the light off for a while. If wiring or the solenoid is at fault, the code will return and the transmission will keep misbehaving.

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.