01 Troubleshooting Coolant Mixing with Oil in Your Engine: Cau… • 02 People Left Concerned After Learning Why Some Hybrids Rando… • 03 All-Wheel Drive vs. Four-Wheel Drive: Navigating Different … • 04 P0050, P0051, and P0052: H02S heater control circuit (Bank … • 05 Most Owners Don’t Realize Their Infotainment Screens Are Se… • 06 Overheating, Misfires, and More: Common Engine Problems Cau… • 07 What is the Purpose of Hazard Lights and How to Use Them Pr… • 08 Engineers Reveal Why Most Car Doors Are Designed To Rip Apa… • 09 Is it cheaper to run a generator on gas or propane? • 10 Should You Admit Fault in a Car Accident if It's Your Fault? •

DTC codes / BMW codes / P1624

P1624 · BMWPedal Position Sensor Potentiometer Supply Channel 1 Electrical

P1624 on BMW vehicles indicates that the engine control module (DME) has detected an electrical fault in the supply channel for the accelerator pedal position sensor potentiometer number 1. The computer monitors the voltage and current on the reference circuit that feeds the sensor, and it sets this code when the signal falls outside the expected range or the circuit is open or shorted.

SystemPowertrain
Code typeBMW specific
SeverityMedium
Fix difficultyIntermediate
AreaComputer and output circuits

Symptoms you may notice

  • The check engine light or electronic throttle control warning light illuminates on the dashboard.
  • The engine may enter limp mode, limiting power and engine speed to a low threshold.
  • The accelerator pedal may feel unresponsive or require excessive travel to accelerate.
  • In some cases, the engine may stall or hesitate when the pedal is pressed.
  • Often no symptoms besides the warning light, especially if the fault is intermittent.

Common causes, most likely first

  1. A faulty accelerator pedal position sensor (potentiometer) internally shorted or open.
  2. Damaged or corroded wiring harness between the pedal sensor and the DME.
  3. Loose or corroded electrical connector at the pedal sensor or DME.
  4. A blown fuse or relay that supplies power to the sensor circuit.
  5. Water intrusion into the pedal sensor connector or wiring, causing corrosion.
  6. A defective DME (rare but possible) with an internal driver fault for the sensor supply.

How to diagnose and fix it

  1. Use a BMW-specific scan tool to read live data from the accelerator pedal sensor and compare both potentiometer signals for plausibility.
  2. Visually inspect the pedal sensor connector and wiring for corrosion, chafing, or loose pins, and repair as needed.
  3. Check the fuse and relay that supply power to the pedal sensor circuit and replace any failed components.
  4. Measure the reference voltage and ground at the sensor connector with a multimeter; if voltage is missing, trace the circuit back to the DME.
  5. Perform a wiggle test on the harness while monitoring live data to identify intermittent wiring faults.
  6. If the sensor is faulty, replace the accelerator pedal assembly and clear the code, then perform a throttle adaptation reset.
  7. If all external circuits test good, diagnose the DME for internal supply channel failure before replacement.

Before you replace the accelerator pedal

  • A common misdiagnosis is replacing the accelerator pedal when the real problem is a corroded connector or chafed wire in the harness near the pedal assembly.
  • The DME supplies a 5-volt reference to the potentiometer; a short to ground or to voltage on that line will set P1624 even if the sensor itself is good.
  • Intermittent faults often occur due to water ingress from a leaking windshield or cowl drain, which corrodes the pedal sensor connector.
  • This code can be set by a low battery or charging system issue that causes voltage spikes, so always check battery health and charging voltage first.
  • On some BMW models, the pedal sensor is integrated into the pedal assembly and cannot be replaced separately, but the wiring and connectors are still serviceable.

Can I keep driving with P1624?

If the vehicle is in limp mode, driving is not recommended because power is severely limited and unpredictable. If the check engine light is on but the car drives normally, you can drive cautiously to a repair shop, but avoid sudden acceleration or heavy loads until the fault is repaired.

Tools that help

Tools we recommend are in the Auto Veteran shop on Amazon. As an Amazon Associate we earn from qualifying purchases.

Guidance is general and written for BMW vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.

Running on fumes Free guides aren't free to make. Top up the tank. Any amount, one time. Fuel the Garage