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Information only. This page provides general educational information about fault code P1639. We do not assess the urgency or safety implications of any specific fault. That requires in-person diagnosis by a qualified mechanic. Full terms.

Recommended next steps

Whether a fault is urgent, drivable, or routine depends entirely on the cause on a specific vehicle, and that can only be determined by a qualified mechanic with diagnostic equipment. If a warning light is illuminated, the most reliable next step is professional diagnosis.

What does P1639 mean?

P1639 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: Accelerator Pedal Position Sensor 1+2 Range/Performance.

Manufacturer-specific notes

Some manufacturers publish additional definitions or variations for this code. Always cross-check with your vehicle's own service documentation.

Acura Accelerator Pedal Position Sensor 1+2 Range/Performance
Audi Accelerator Pedal Position Sensor 1+2 Range/Performance
BMW Accelerator Pedal Position Sensor 1+2 Range/Performance
Cadillac 5-Volt Reference 2 Circuit Malfunction
Chevrolet 5-Volt Reference 2 Circuit Malfunction
Ford Accelerator Pedal Position Sensor 1+2 Range/Performance
GMC 5-Volt Reference Circuit Low Input
Honda 5-Volt Reference Voltage 'B' Circuit Malfunction
MINI Accelerator Pedal Position Sensor 1+2 Range/Performance
Mazda Generator Battery Terminal Open Circuit Malfunction
SEAT Accelerator Pedal Position Sensor 1+2 Range/Performance
Skoda Accelerator Pedal Position Sensor 1+2 Range/Performance
Vauxhall Accelerator Pedal Position Sensor 1+2 Range/Performance
Volkswagen Accelerator Pedal Position Sensor 1+2 Range/Performance

About Electrical & Sensors codes

Codes in the Electrical & Sensors category.

P1639 is one of 4,010 codes in this category. Browse all Electrical & Sensors codes →

What we know about P1639 specifically

We record the SAE J2012 standardised definition and the system this code belongs to, but we have not yet published detailed driver-reported symptoms, common causes, or step-by-step diagnostic guidance for P1639.

Rather than invent that information by generating generic content from a template, we leave it out. For specific guidance, the most reliable sources are:

  • your vehicle's own service manual or manufacturer-specific technical bulletins
  • a qualified mechanic with a manufacturer-level diagnostic tool
  • a marque specialist familiar with your make and model

Spotted an issue or have something to add? Mechanics, technicians, and drivers who have first-hand experience with P1639 can submit a correction or expansion. We review every submission before publishing, mechanic submissions are prioritised.

Information only, not professional advice

The information on this page is provided for general guidance and educational purposes only. It is not a substitute for diagnosis or repair advice from a qualified mechanic. Always verify any fault before paying for repairs. carfaultcodes.co.uk accepts no liability for decisions made based on this information. Full terms →

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