P2139 critical

Throttle/Pedal Position Sensor/Switch D/F Voltage Correlation

The P2139 code means the vehicle's onboard diagnostic system has detected: Throttle/Pedal Position Sensor/Switch D/F Voltage Correlation. This is a critical severity code.

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Keep driving?: Short distances only
DIY difficulty: hard
Estimated cost: $100 - $700 (parts and labor)

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Common Symptoms

Reduced engine power
Throttle does not match pedal input
Delayed or inconsistent acceleration
Limp mode active
Check engine light on

Probable Causes (Ranked by Likelihood)

APP sensor D output not matching TPS F output from throttle body Very High
Carbon buildup on throttle body causing position error High
Faulty electronic throttle body TPS Moderate
Faulty accelerator pedal position sensor Moderate
Wiring issue in either D or F circuit Low

Step-by-Step Diagnostic Procedure

Compare APP sensor D reading to TPS F reading with scan tool -- they should show consistent relationship
Clean throttle body to ensure TPS F reads accurately
Test APP sensor D by pressing pedal slowly -- signal should be smooth and consistent
Check both sensor connectors for corrosion or damage
If cleaning does not resolve, determine which sensor (pedal or throttle body) has the incorrect reading

Frequently Asked Questions

Can I drive with code P2139?

Only short distances. The PCM has detected a mismatch between pedal position and throttle body position, meaning the throttle is not going where the pedal tells it. The vehicle will have limited power.

Could this be a pedal problem or a throttle body problem?

It could be either. The D circuit is on the pedal and the F circuit is on the throttle body. You need to determine which sensor is reading incorrectly by comparing each to its companion sensor (D compared to E, and F compared to the primary TPS).

Why does the PCM compare pedal position to throttle position?

The PCM cross-references pedal position with actual throttle position to verify the electronic throttle system is working correctly. If the pedal says 50% but the throttle is only at 20%, something is wrong and the PCM limits power to prevent unsafe conditions.