P0826 - UP AND DOWNSHIFT SWITCH CIRCUIT

Diagnostic code P0826 OBD2 is set when the Powertrain Control Module (PCM) finds a malfunction in the electrical circuits of the up/downshift switch, which operates in conjunction with the transmission range correlation circuit.

The shift system allows the driver to manually shift automatic gears. Proper activation of this system would initiate an up or downshift, taking into account the proper signals from the Transmission Control Module (TCM).

• Check Engine light illuminated.
• Transmission shifts abruptly.
• The torque converter lock-up function is not available.
• Transmission goes into emergency mode.

The reasons for storing the P0826 OBDII fault code are:

• Maybe the transmission mode selector switch is faulty.
• Perhaps the shift lever is stuck or damaged.
• The system wires could have an open or short circuit.

Troubleshooting steps for DTC P0826 OBD2 are:

• Inspect all wiring and electrical connectors on the transmission mode selector switch. Look for obvious damage such as burns, wear, or corrosion. Replace any of these components as required.
• Verify that all wiring related to the system has reference voltage and ground signals. Refer to the manufacturer's data. Make the necessary adjustments.
• Check for continuity at the system connectors. Check with the wiring diagram to confirm that the electrical values you obtained are within the manufacturer's specifications. Repair as necessary.
• If after performing the above repairs, the P0826 code still appears, drive the vehicle and manually activate the shift switch. If it is not possible to do so, you should replace it.