P0756 - SHIFT SOLENOID "B" PERFORMANCE / STUCK OFF

The automatic transmissions have three-shift solenoids. These solenoids control the movement of transmission fluid through the various hydraulic circuits. In this way, the ratio is changed at the required time and the engine performance is improved.

To shift gears, the transmission depends on precise fluid pressure for the transmission belts and clutches to do their job properly. Solenoids open and close the valves to allow fluid to flow to the clutches and belts.

When the Powertrain Control Module (PCM) detects a malfunction in the transmission solenoid “B” circuit, some DTCs may be activated. In this case, the diagnostic code P0756 OBDII refers to a lock-up condition or problem in the “B” solenoid performance.

• Check Engine light ON.
• The transmission overheats.
• Transmission slippage.
• Fuel efficiency decreases.
• You may experience symptoms similar to misfiring.
• The vehicle enters failsafe mode.

The causes of DTC P0756 OBD2 are:

• Perhaps the transmission fluid has contaminants in it.
• There may be an excessively low level of transmission fluid.
• Hydraulic system lines may be clogged.
• The "B" shift solenoid wires or connectors may be faulty.
• The shift solenoid "B" may be defective.

Steps to troubleshoot the P0756 OBDII fault code:

• When starting any diagnostics, it is recommended to check the TSBs (Technical Service Bulletins).
• Check that the transmission fluid is not dirty or contaminated. Also, make sure the fluid level is adequate for the proper transmission operation. Make the necessary corrections.
• Check the solenoid circuit wiring and connectors for damage that causes the circuit to malfunction. Burned or worn wires should be repaired or replaced. Also, test the wires for continuity and check for any level of resistance. A lack of continuity indicates a short circuit. Repair if necessary.
• Replace shift solenoid "B".