The torque converter clutch pulse width modulation solenoid is responsible for helping to engage the torque converter clutch. If it does not work properly, then the torque converter clutch could get stuck, resulting in poor engine performance or engine stalling. Should this happen, a P1860 diagnostic trouble code a will we be stored in the TCM/ECU.
How Serious is the Code?
The P1860 DTC is a fairly serious OBDII diagnostic trouble code, as it relates to the operation of the torque converter. Should this not work properly, the engine can fail to perform or completely stall out, which can create a serious safety hazard.
Symptoms of a P1860 include:
- Engine stalling
- Poor engine performance
- Failed upshifts/downshifts
- Transmission overheating
- Faulty TCC PWM solenoid
- Dirty transmission fluid/filter
- Blocked hydraulic passage inside the transmission
How to Diagnose the Code?
The condition of the transmission fluid is the first thing that should be considered when diagnosing a P1860 DTC. If the condition of the ATF is good and no metal fragments are present, electrical tests will need to be performed on the torque converter clutch pulse width modulation solenoid.
What Repairs Will Fix P1860?
- Service the transmission (i.e. change the transmission fluid and filter)
- Replace the TCC PWM solenoid
P1866 – TCC PWM Solenoid Circuit Low Voltage