P0826 Fault Code

Up and Down Switch Input Circuit

• What does that mean?
• Symptoms
• Causes
• Solutions

The P0826 fault code refers to an issue in the Up and Down Switch Input Circuit, which is responsible for detecting the operator's input for gear shifting. This circuit includes the switches that indicate whether to shift up or down in a vehicle with an automatic transmission. Proper functioning of this circuit is critical for seamless gear transitions and overall transmission performance.

What are the symptoms of the P0826 code?

Symptoms associated with a P0826 fault code may include:

• Inability to shift gears correctly
• Transmission might go into 'limp mode'
• Unusual behavior when attempting to shift up or down
• Dash warning lights illuminated, such as the check engine light
• Harsh or erratic shifting patterns.

What causes the P0826 code?

Common causes of the P0826 code include:

• A malfunctioning up and down switch
• Poor electrical connections or corroded wiring in the circuit
• A defective transmission control module (TCM)
• Internal transmission issues that affect switch operation
• Faulty vehicle speed sensors that lead to erratic behavior of the switch inputs.

How to fix P0826?

To resolve the P0826 fault code, consider the following steps:

• Inspect and repair any damaged or corroded wiring connections in the up and down switch circuit.
• Test the up and down switches for proper functionality and replace if necessary.
• Check for issues with the transmission control module and reprogram or replace as needed.
• Inspect the vehicle speed sensors and replace them if they are not functioning correctly.
• Clear the fault code and take the vehicle for a test drive to ensure the issue is resolved.