Diagnostic trouble code (DTC) information

Condition 

Fig 1: Identifying Accelerator Pedal (AP) Position Sensor

Courtesy of VOLVO CARS OF NORTH AMERICA.

Diagnostic trouble code (DTC) ECM-9520 is stored if the engine control module (ECM) registers a fault in the analog signal from the accelerator pedal (AP) position sensor with the ignition is switched on.

Substitute Value 

The accelerator pedal (AP) is not working at all at the same time as the brake pedal is pressed.

Possible Source 

Signal too high: 

• Short-circuit to supply voltage in the signal cable
• Defective accelerator pedal (AP) position sensor.

Signal too low: 

• Contact resistance or oxidation in the terminals between the engine control module (ECM) and the accelerator pedal (AP) position sensor
• Open-circuit in the power supply (12 V) for the accelerator pedal (AP) position sensor
• Open-circuit in the power supply (5V) for the analog signal
• Open-circuit in the signal ground cable for the analog signal
• Open-circuit or short-circuit to ground in the signal cable
• Defective accelerator pedal (AP) position sensor.

Faulty signal: 

• Open-circuit in the power supply (12 V) for the accelerator pedal (AP) position sensor
• Water in the connectors.
• Defective accelerator pedal (AP) position sensor.

Fault symptom[s] 

• Poor accelerator pedal (AP) response.