The transmission fluid is what moves parts around inside the gearbox, thanks to the hydraulic pressure created by the engine. If the ECU thinks that the transmission fluid pressure is too high, it will save a P0869 DTC.
How Serious is the Code?
Having a P0869 diagnostic trouble code is very serious, because it can affect both the drivability of your vehicle, and cause serious damage to the internal transmission parts. Needless to say, a mechanic should diagnose the problem immediately.
Symptoms of a P0869 include:
- Overheating transmission
- Smoke/smell coming from the transmission
- Transmission slipping
- Transmission will not engage gears
- Low or dirty transmission fluid
- Transmission fluid leaks
- Damaged connectors and/or wiring
- Overheated transmission
- Overheated engine
- Malfunctioning transmission pump
- Malfunctioning transmission fluid pressure sensor
- Malfunctioning transmission fluid temperature sensor
How to Diagnose the Code?
Dirty or low transmission fluid is one of the leading causes of a P0869 OBDII trouble code. Transmission fluid leaks can also cause this OBD2 error code, as can wiring the damage and broken connectors. Transmission fluid pressure sensor and transmission fluid temperature sensor may also need to be checked. If none of these transmission problems are present, an in-depth internal diagnosis will be needed to determine if the problem lies with the transmission pump, or another mechanical part.
What Repairs Will Fix P0869?
- Change the transmission fluid and filter
- Repair transmission fluid leaks
- Repair or replace damaged wiring and sensors on the transmission wiring harness
- Replace the transmission pump
- Replace transmission fluid pressure sensor
- Replace transmission fluid temperature sensor
- Replace or repair transmission
- P0867 – Transmission Fluid Pressure
P0868 – Transmission Fluid Pressure Low