Transmission Fluid Pressure Sensor/Switch D Circuit Low
What does P0877 mean?
The P0877 code means the vehicle's onboard diagnostic system has detected: Transmission Fluid Pressure Sensor/Switch D Circuit Low. This is a moderate severity code.
Common Symptoms
- Check Engine Light illuminated
- Slipping during specific gear changes
- Delayed engagement in certain gears
- Transmission may limit gear range
Probable Causes (Ranked by Likelihood)
- Short to ground in pressure sensor D signal wire Very High
- Faulty pressure sensor D producing low voltage High
- Corroded connector at sensor D Moderate
- Low transmission fluid level Moderate
Step-by-Step Diagnostic Procedure
-
Check transmission fluid level first
-
Measure voltage at pressure sensor D connector
-
Test for short to ground in the signal wire
-
Replace sensor D if wiring and fluid are confirmed good
Frequently Asked Questions
Can I check the fluid level myself?
Many modern vehicles no longer have a traditional dipstick. Check your owner's manual for the correct fluid level check procedure, which may require a scan tool on some models.
Is sensor D in a hard-to-reach location?
Sensor D location varies by transmission. On some models it is externally accessible, while on others it may require removing the transmission pan or valve body.
Can a leak at the sensor cause P0877?
A leak at the sensor seal can lower local pressure and also allow fluid to reach the connector, potentially causing a short. Inspect the area around the sensor for wetness.