What does it mean?
P1876 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: Up and Down Shift Enable Switch Circuit Low Voltage .
Symptoms
- Malfunction indicator lamp on and manual shift mode unavailable
- Paddle or gate shifts work only in one direction, or not at all
- Gear display on the dash stuck on one gear or blank in manual mode
- Transmission stays in fully automatic mode regardless of the shifter position
- Unrequested upshifts or downshifts if the input is being read as pressed
- Other steering wheel controls may misbehave when the clock spring is at fault
Likely causes
- Switch contacts shorted internally or stuck closed
- Control wire shorted to ground along the console or steering column
- Liquid spilled into the centre console reaching the shifter connector
- Harness damaged at a flex point behind the shifter boot or in the steering column
- Worn clock spring where the paddle shifters route through the column
- Loose or corroded terminal at the shifter assembly connector
- Faulty input circuit in the transmission control module
How to fix it
- Read codes and identify from live data whether it is the up or the down input that reads low
- Operate the switch or paddles while watching the input state in live data
- Inspect the shifter and column connectors for liquid damage, corrosion and green terminals
- Measure the switch resistance in both the released and pressed states
- Disconnect the switch and check the control circuit for a short to ground — a short with the switch removed proves a harness fault
- Inspect the clock spring and its wiring where paddles are fitted
- Repair the harness or replace the switch assembly; consider the module only after both test good