To change gears in line with driving conditions, the ECU has to be able to modulate the hydraulic pressure inside of the transmission. It does this with the pressure control solenoid(s), but the decision is made using data from the hydraulic pressure sensor. If this transmission sensor is not performing within its expected range, a P0933 DTC will be triggered.
How Serious is the Code?
If the ECU cannot determine what the hydraulic pressure is currently inside the transmission, the performance of the transmission and vehicle will both suffer greatly. So yes, a P0933 diagnostic trouble code is very serious.
Symptoms of a P0933 include:
- Unusually firm shifts when the RPMs are low
- Unusually soft shifts under load when the RPMs increase
- Lower acceleration power than usual (because the transmission was told to start in 2nd instead of 1st)
- The engine fails to upshift at speed (caused the ECU has locked out higher gears)
- Damage or corrosion in the wiring or connectors
- Defective fuses
- Non-working transmission pressure sensor
- ECU/TCM issues
How to Diagnose the Code?
To diagnose a P0933 OBDII trouble code, any wires or connectors along this circuit will need to be inspected for signs of damaged broken wires/ground wires, and broken or corroded connectors. The transmission pressure sensor itself will also need to be considered, along with the programming of the ECU and possibly TCM.
What Repairs Will Fix P0933?
- 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
- P0934 – Hydraulic Pressure Sensor Circuit Low
- P0935 – Hydraulic Pressure Sensor Circuit High
- P0936 – Hydraulic Pressure Sensor Circuit Intermittent