The hydraulic pressure sensor is a vital transmission part that helps the ECU decide how to change gears. If an unusually high-voltage signal is detected along the hydraulic pressure sensor/line pressure sensor circuit, a P0935 DTC will be set.
How Serious is the Code?
If the vehicle’s computer cannot tell how much hydraulic pressure is the transmission pump is putting out, the transmission, and ultimately the vehicle itself, will not be able to perform properly. Ignoring a P0935 diagnostic trouble code for too long, may also result in serious internal damage.
Symptoms of a P0935 include:
- Unusually hard shifts at lower RPM
- Unusually soft shifts at higher RPM
- Less acceleration (if the transmission starts in 1st instead of 2nd)
- Unusually high RPMs at speed (because the ECU has told the transmission not to upshift)
- Damaged wiring and/or connectors
- Faulty fuses
- Faulty transmission pressure sensor
- ECU/TCM issues
How to Diagnose the Code?
To properly diagnose a P0935 OBDII trouble code, your mechanic should first look at the condition of the wiring and connectors (including ground wires/contacts) along the transmission pressure sensor circuit. They should also check any related fuses and relays. Should nothing be found, the hydraulic pressure sensor/line pressure sensor itself should be tested, along with possibly the ECU and TCM.
What Repairs Will Fix P0935?
- Replace or repair damaged wiring or connectors
- Replace blown fuses
- Replace transmission pressure sensor
- Replace or reprogram ECU or TCM
- P0932 – Hydraulic Pressure Sensor Circuit
- P0933 – Hydraulic Pressure Sensor Range/Performance
- P0934 – Hydraulic Pressure Sensor Circuit Low
- P0936 – Hydraulic Pressure Sensor Circuit Intermittent