Up and Down Shift Switch to Transmission Range Correlation
What does P0819 mean?
The P0819 code means the vehicle's onboard diagnostic system has detected: Up and Down Shift Switch to Transmission Range Correlation. This is a moderate severity code.
Common Symptoms
- Check Engine Light illuminated
- Manual shift mode does not match expected gear
- Transmission may not respond to manual shift inputs
- Erratic shifting when using sport or manual mode
Probable Causes (Ranked by Likelihood)
- Misadjusted or faulty transmission range sensor Very High
- Shift switch input not matching range sensor position High
- Wiring fault in shift switch or range sensor circuit Moderate
- TCM correlation logic error requiring software update Low
Step-by-Step Diagnostic Procedure
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Compare shift switch inputs to transmission range sensor data on a scan tool
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Check the transmission range sensor adjustment
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Inspect wiring for both the shift switch and range sensor circuits
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Verify TCM software is at the latest calibration
Frequently Asked Questions
What does correlation mean in P0819?
Correlation means the TCM compares signals from two sources. In this case, the shift switch input does not agree with the transmission range sensor position, indicating a mismatch.
Can a software update fix P0819?
In some cases, a TCM software update can correct correlation logic issues. Check with your dealer for applicable technical service bulletins.
Should I replace both the shift switch and range sensor?
Not necessarily. Diagnose which component is giving the incorrect reading first. Replacing only the faulty component will save money.