Code Definition

P1285 — Accelerator pedal position sensor 3 circuit fault

System: Powertrain  |  Type: Manufacturer-Specific  |  Make: Isuzu

About P1285

P1285 is a manufacturer-specific powertrain diagnostic trouble code recorded for Isuzu vehicles. It belongs to the P-prefix family of codes, which covers engine, transmission, emissions, or fuel-system faults.

When P1285 is stored, the module has detected a sensor-related fault — the reported value from the named sensor is out of spec.

Scanning & clearing: A generic OBD-II scan tool will usually read and clear powertrain (P) codes. For live data, freeze-frame capture, and bi-directional tests you may need a more capable scan tool that supports the vehicle's ECM protocol.

P1285 is a manufacturer-specific code. The same code string on a different make may have a different meaning. Always confirm the code's definition against the vehicle's service information for the specific make and model under test.

Code Information

The accelerator pedal position sensor 3 provides the ECM with a third redundant signal of pedal travel in the electronic throttle system, cross checked against sensors 1 and 2. DTC P1285 sets when the ECM detects a fault in the sensor 3 circuit, where the signal is out of its normal range, open, shorted, or implausible. Sensor 3 uses its own 5 volt reference and ground and returns a signal voltage proportional to pedal position. When the circuit fails the ECM loses a layer of redundancy and limits engine power, so the driver experiences reduced power, poor throttle response, and a forced idle ...

Join TaT to view the complete code information and diagnostic details.

Quick Facts