A transmission fluid pressure sensor/transmission line pressure sensor tells the ECU how much hydraulic pressure is available inside the transmission at any given time. A P0987 DTC means that there is a problem somewhere along the circuit between the ECU and the TFPS switch.
How Serious is the Code?
Unless the computer knows how much hydraulic pressure is available to make a shift, transmission performance will be severely compromised. So a P0987 diagnostic trouble code is extremely important.
Symptoms of a P0987 include:
- Gear changes are extremely harsh
- Transmission may not shift into gear
- Limp Mode
- Dirty or low transmission fluid
- Damaged wiring/connectors
- Failed transmission fluid pressure sensor/line pressure sensor
- Valve body issues
How to Diagnose the Code?
When diagnosing a P0987 OBDII trouble code, the first thing that should be done is check the level and condition of the transmission fluid. Next, the wiring and connectors along the transmission wiring harness should be carefully examined for signs of damage and corrosion. If no issues are found, then the transmission fluid pressure switch itself will need to be tested. If that checks out, then there may be further mechanical issues, like valve body problems, that could trigger this OBD2 code.
What Repairs Will Fix P0987?
- Add or change transmission fluid and filter
- Repair or replace damaged wiring and connectors
- Replace transmission fluid pressure sensor/switch
- Repair or install remanufactured valve body
- P0988 – Transmission Fluid Pressure Sensor/Switch “E” Circuit Range/Performance
- P0989 – Transmission Fluid Pressure Sensor/Switch “E” Circuit Low
- P0990 – Transmission Fluid Pressure Sensor/Switch “E” Circuit High.
- P0991 – Transmission Fluid Pressure Sensor/Switch “E” Circuit Intermittent