Up and Down Shift Switch Circuit High
What does P0828 mean?
The P0828 code means the vehicle's onboard diagnostic system has detected: Up and Down Shift Switch Circuit High. This is a low severity code.
Common Symptoms
- Check Engine Light illuminated
- Manual shift mode unavailable
- Shift switch always reads as released
- TCM does not respond to manual shift inputs
Probable Causes (Ranked by Likelihood)
- Open circuit in shift switch wiring Very High
- Disconnected or damaged shift switch connector High
- Faulty shift switch stuck in open position Moderate
- TCM reference voltage issue on switch input Low
Step-by-Step Diagnostic Procedure
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Check for an open circuit in the shift switch signal wire
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Verify connector is fully seated at the shift switch
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Test switch operation with a multimeter for proper continuity when pressed
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Check TCM reference voltage at the switch connector
Frequently Asked Questions
What does circuit high mean for P0828?
Circuit high means the voltage on the shift switch signal is above the expected maximum. This usually indicates an open circuit where the signal wire is pulled up to reference voltage because the ground path through the switch is broken.
Is P0828 the opposite of P0827?
Yes. P0827 indicates the circuit is shorted low while P0828 indicates it is open or shorted high. The diagnostic approach is similar but focuses on different types of faults.
Can I drive normally with P0828?
Yes, the transmission will operate normally in automatic mode. Only the manual shift function is affected.