Transmission Range Sensor Circuit Intermittent (Ford)
What does P1702 mean?
The P1702 code means the vehicle's onboard diagnostic system has detected: Transmission Range Sensor Circuit Intermittent (Ford). This is a moderate severity code.
Common Symptoms
- Check Engine Light on
- Incorrect gear indicator on dashboard
- Transmission shifting erratically
- Vehicle starting in wrong gear
- Backup lights not working correctly
Probable Causes (Ranked by Likelihood)
- Faulty transmission range sensor (TRS) Very High
- Loose or corroded TRS connector High
- Misadjusted manual shift linkage Moderate
- Damaged wiring between TRS and PCM Low
Step-by-Step Diagnostic Procedure
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Use a scan tool to read the TRS signal while slowly moving the shifter through each gear position.
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Inspect the TRS connector on the transmission for corrosion, loose fit, or fluid contamination.
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Check the shift cable or linkage adjustment. Improper adjustment can cause the TRS to read between positions.
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Measure TRS resistance or voltage at each gear position and compare to Ford specifications.
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If the sensor is mounted externally, check for proper alignment and mounting bolt torque.
Frequently Asked Questions
What is the transmission range sensor?
The TRS tells the PCM which gear the shifter is in (Park, Reverse, Neutral, Drive, etc.). It is also called the neutral safety switch on some vehicles.
Can I adjust the TRS instead of replacing it?
Sometimes. If the sensor is misaligned due to linkage issues, adjusting the shift cable and re-centering the TRS may fix the problem.
Why does my gear indicator show the wrong gear?
An intermittent TRS signal sends incorrect gear position data to the PCM, which causes the wrong gear to display on the dashboard.