Transmission Park Position Sensor/Switch "A"/"B" Correlation
This code means the PCM/ECM has detected a correlation mismatch between related signals affecting transmission park position sensor/switch "a"/"b. When this happens, the transmission may not control clutch apply pressure or gear changes correctly, which can lead to harsh shifting, slipping, delayed engagement, or fail-safe mode.
What You Might Notice
- Check Engine Light illuminated
- Harsh or delayed shifting
- Transmission slipping or wrong gear feel
- Vehicle may enter limp mode
- Poor acceleration
Most Common Causes
- 1
Faulty solenoid, pressure sensor, or actuator
- 2
Damaged wiring or poor connector contact
- 3
Low, dirty, or incorrect transmission fluid
- 4
Internal valve body or clutch problem
- 5
Fault in the TCM/PCM or calibration
How to Diagnose It
- 1
Check Faulty solenoid, pressure sensor, or actuator — Inspect for signs of failure and test before replacing.
- 2
Check Damaged wiring or poor connector contact — Inspect for signs of failure and test before replacing.
- 3
Check Low, dirty, or incorrect transmission fluid — Inspect for signs of failure and test before replacing.
- 4
Check Internal valve body or clutch problem — Inspect for signs of failure and test before replacing.
- 5
Check Fault in the TCM/PCM or calibration — Inspect for signs of failure and test before replacing.
How to Fix It
- 1
Verify the code with scan data and freeze-frame information
- 2
Check transmission fluid level and condition
- 4
Repair damaged wiring or poor connections
- 5
Perform relearn procedures or deeper hydraulic/internal diagnosis if needed
Need a deeper diagnosis?
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