Transmission Fluid Pressure Sensor/Switch D Circuit Low
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.
- Keep driving?
- Short distances only
- DIY difficulty
- hard
- Estimated cost
- $100 - $500 (parts and labor)
Read and clear transmission codes. Many trans codes are caused by low or burnt fluid -- check level and color before assuming the worst.
Basic scanners only read engine codes. This reads transmission, ABS, and airbag too.
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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
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.
Mechanics Guide Step-by-step diagnosis
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
Sources 2
This page is built from documented references. Verify against your own service info before repair work.
- SAE J2012Diagnostic Trouble Code Definitions (defines the generic OBD-II code ranges)
- Cross-checked against the SAE J2012:2002 DTC table (2026-08-27)archived scan of the SAE standard — readable copy, not SAE’s current edition
Commonly Affected Vehicles
- 2017-2020 Ford Explorer (10R80)
- 2015-2019 GM Tahoe (8L90)
- 2014-2020 Jeep Grand Cherokee (ZF 8HP)
- 2016-2020 Acura MDX
Related Codes
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