The ECU has to know how much transmission fluid pressure there is, so it can decide on the right shift strategy. If this signal coming back from the transmission fluid pressure sensor is only intermittent, a P0844 DTC will be saved.
How Serious is the Code?
A P0844 diagnostic trouble code is actually rather serious, and can result in a number of transmission problems that could impact the drivability of your vehicle. These issues include erratic shifting, torque converter problems and transmission overheating.
Symptoms of a P0844 include:
- Harsh, erratic shifts
- Transmission not able to shift gears
- Non-working torque converter clutch
- Transmission overheating
- Reduced fuel economy
- Insufficient transmission fluid
- Dirty transmission fluid / filter
- Transmission fluid leak
- Frayed wiring / damaged connectors
- Failed transmission fluid pressure sensor
- Failed transmission pump
- Torque convertor issue
- Pressure control solenoid failure
- Pressure regulator failure
- Internal pressure problems
- Valve body issue
- TCM failure
How to Diagnose the Code?
The first step when diagnosing a P0844 OBDII trouble code, should be to check the level and condition of the transmission fluid. Not having enough transmission fluid, dirty transmission fluid can actually affect the hydraulic fluid pressure and performance of the transmission fluid pressure sensor. If no issues are found, the wiring and connectors on the transmission wiring harness will need to be inspected. If nothing is found by this point, then dipped mechanical diagnostics will be needed.
What Repairs Will Fix P0844?
- Change transmission fluid and filter
- Repair leaks
- Repair or replace damaged wiring and connectors
- Replace transmission fluid pressure sensor
- Repair or replace torque converter
- Repair or replace valve body
- Replace transmission pump
- Replace pressure control solenoid
- Replace pressure regulator
- Reprogram or replace TCM