P3066moderate severityPowertrain
Transmission Range Sensor Rationality Error
on 2002 Mazda Protege5 2.0L I4 · FWD
What this code means
The transmission range sensor (TRS) reading does not agree with other inputs such as gear state solenoids and output shaft speed.
Symptoms
- Check Engine Light
- Incorrect gear displayed on dash
- Transmission may not shift out of park
- Backup lights on in drive
- Wrong gear engagement
- Intermittent no-start in Park
Common causes
- TRS misadjusted
- TRS internal failure
- Shift linkage loose or worn
- TRS connector corroded
- TRS wiring short
Diagnostic steps
- Compare TRS signal to actual gear selector position
- Inspect shift linkage adjustment
- Test TRS voltage in each gear position
- Check TRS connector
- Monitor TRS signal for dropouts
Repair notes
Adjust or replace transmission range sensor. Check and adjust shift linkage. Verify correct gear display in all selector positions.
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