P1860moderate severityPowertrain
TCC PWM Solenoid Circuit Electrical
on 2010 GMC Terrain 2.4L I4 · FWD
What this code means
The PCM/TCM detected a continuous open, short to ground, or short to power in the Torque Converter Clutch (TCC) Pulse Width Modulation (PWM) solenoid valve circuit. The TCC PWM solenoid controls smooth engagement of the torque converter clutch by varying duty cycle. Normal solenoid resistance is 10-16 ohms.
Symptoms
- Check Engine Light
- Transmission slipping
- Harsh shifting
- No torque converter lockup
- Reduced fuel economy
- Bucking feeling at highway speed
- Transmission overheating
Common causes
- Failed TCC/PWM solenoid (most common)
- Broken or corroded wiring to solenoid
- Short in wire harness
- Faulty PCM/TCM
- Poor electrical connection at transmission connector
- PCM software needing update
Diagnostic steps
- Test TCC PWM solenoid resistance (should be 10-16 ohms)
- Check for open, short to ground, or short to power on solenoid circuit
- Inspect transmission connector for damage
- Clear codes and road test
- Test PCM solenoid driver output
Repair notes
Check solenoid resistance first. Replace TCC PWM solenoid if out of spec. Inspect transmission connector and wiring. Solenoid is accessible by removing transmission pan and valve body.
Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1
P0011
Intake Camshaft Position Timing Over-Advanced Bank 1
P0012
Intake Camshaft Position Timing Over-Retarded Bank 1
P0013
Exhaust Camshaft Position Actuator Circuit/Open Bank 1
P0014
Exhaust Camshaft Position Timing Over-Advanced Bank 1
P0015
Exhaust Camshaft Position Timing Over-Retarded Bank 1