In order to control the pressurized transmission fluid inside the valve body, the ECU uses a number of little devices called pressure control solenoids. Their job is to maintain the proper amount of hydraulic pressure by opening or closing, thereby allowing the operation of the different clutches and gear sets. If a high voltage signal is detected (usually signifies an electrical problem), a P2739 DTC will be set.
How Serious is the Code?
The P2739 diagnostic trouble code is actually quite serious, because it means the computer is not fully in control of the transmission. This means there will be enough hydraulic pressure to allow the transmission to shift properly. When this happens you can experience a number of transmission problems, including delayed shifts, unusually hard shifts, and even engine stalling.
Symptoms of a P2739 include:
- Erratic shifts
- Hard shifts
- Delayed shifts
- Engine stalls while stopped in gear
- Vehicle won’t move when in gear
- Transmission overheats
- Increased fuel consumption
- Limp mode
- Dirty transmission fluid / filter
- Not enough transmission fluid
- Frayed wiring / damaged connectors
- Failing pressure control solenoid
- Failing transmission pump
- Internal pressure problems
- Valve body issue
- ECU or TCM failure
How to Diagnose the Code?
When you start trying to diagnose a P2739 OBDII diagnostic trouble code, you should start with the level and condition of the transmission fluid. If it’s too low or dirty, the transmission control solenoid will not operate properly. If there are no problems with the transmission fluid, then the wiring and connectors on the transmission wiring harness checked for damage and corrosion. If you’ve found no problems by this point, then the pressure control solenoid, transmission pump, valve body and possibly the ECU/TCM should be checked.
What Repairs Will Fix P2739?
- Changing the fluid and filter
- Replace faulty pressure control solenoid
- Repair or replace a faulty transmission pump
- Repair or replace defective transmission valve body
- Transmission flush to clean passages
- Cleaning corrosion from connectors
- Repairing or replacing wiring
- Flashing or replacing PCM
- P2722 – Pressure Control Solenoid E
- P2723 – Pressure Control Solenoid E Perf or Stuck Off
- P2724 – Pressure Control Solenoid E Stuck On
- P2725 – Pressure Control Solenoid E Electrical
- P2726 – Pressure Control Solenoid E Intermittent
- P2727 – Pressure Control Solenoid E Ctrl Circ / Open
- P2728 – Pressure Control Solenoid E Ctrl Circ Range/Perf
- P2730 – Pressure Control Solenoid E Ctrl Circ High