What does it mean?
P1862 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: TCC Solenoid Circuit Malfunction .
Symptoms
- Check engine lamp on, often together with converter lockup complaints
- Engine stalls when slowing to a stop because the converter stays applied
- No lockup at cruise, so engine speed and fuel consumption stay high
- Shudder or vibration during light-throttle cruising
- Transmission fluid running hotter than normal and limp mode in some cases
Likely causes
- Solenoid winding open or shorted internally after heat and mileage
- Control wire broken or shorted to ground inside the transmission on the internal harness
- Transmission case connector corroded or wicking fluid between its terminals
- External harness chafed against the case, a bracket or an exhaust component
- Solenoid valve stuck with varnish or debris so lockup cannot release
- Low or contaminated fluid affecting apply pressure
- Module output driver damaged after a solenoid short
How to fix it
- Read all codes and the freeze frame, and inspect fluid level, colour and smell
- Check the case connector for fluid, corrosion and terminal tension, and follow the external harness for chafe
- Measure the solenoid resistance at the case connector and compare with specification
- Test the control wire from the module to the case connector for continuity and shorts
- Command lockup on and off with the scan tool while watching engine rpm and slip on a road test
- Drop the pan, inspect the internal harness and solenoid, and check the pan magnet for debris
- Replace the solenoid, renew fluid and filter, and verify clean lockup apply and release before returning the vehicle