Faulty accelerator pedal position sensor (internal wear or failure); Poor connection at the pedal sensor connector (corrosion, loose or bent terminals); Damaged wiring between the pedal sensor and ECU (chafing, open circuit, short to earth or voltage); Fault in the sensor supply voltage or earth circuit shared with other sensors; Water ingress or contamination in the pedal assembly or connector; Faulty ECU or throttle control module.

P1246

Accelerator Position Sensor 1 Circuit Malfunction.

Acura
Powertrain
Manufacturer code
Medium severity

How this code is built

P: SystemPowertrain
1: Defined byThe manufacturer
2: AreaFuel and air metering (injector circuit)
46: FaultThe specific fault in that area

What it means

P1246 on an Acura means the engine control unit has detected a fault in the circuit for accelerator position sensor 1, which reports how far the throttle pedal is pressed. The ECU saw a signal voltage outside the expected range, or one that did not agree with the other pedal sensor or with expected values. The exact sensor layout and the way the ECU compares the signals depends on the model and engine.

Symptoms

Malfunction indicator lamp on
Poor or delayed throttle response
Engine held at a reduced idle or limited power (limp mode)
Engine will not rev freely or surges
Hesitation or stumbling when pulling away
Possible rough idle or stalling

Possible causes

Faulty accelerator pedal position sensor (internal wear or failure)likely
Poor connection at the pedal sensor connector (corrosion, loose or bent terminals)likely
Damaged wiring between the pedal sensor and ECU (chafing, open circuit, short to earth or voltage)possible
Fault in the sensor supply voltage or earth circuit shared with other sensorspossible
Water ingress or contamination in the pedal assembly or connectorpossible
Faulty ECU or throttle control modulerare

How to diagnose

Read all stored codes and freeze frame data, and note whether other sensor supply or throttle codes are present
Visually inspect the pedal sensor connector and wiring for damage, corrosion, moisture or signs of rubbing
With a scan tool, watch the live accelerator position sensor values while slowly pressing and releasing the pedal, looking for dropouts, jumps or disagreement between sensor channels
Wiggle the harness and connector while watching live data to find intermittent faults
Check the sensor supply voltage and earth at the connector against the manufacturer's specification for your model
Test the signal wiring for continuity and for shorts to earth or voltage with the ECU and sensor disconnected
Check the pedal assembly for physical damage, sticking or contamination
Clear the code and road test to confirm whether it returns, following the model-specific procedure

How to fix

Replace the accelerator pedal position sensor or pedal assembly if its readings are erratic or out of specification
Clean, repair or replace the connector and terminals if corroded or loose
Repair or replace damaged wiring between the pedal sensor and the ECU
Restore the sensor supply or earth circuit if the voltage check shows a fault
Dry out and seal any water ingress, then replace parts that are damaged by it
Only after everything else is proven good, diagnose the ECU following the manufacturer's procedure

Can I keep driving?

Medium severity

The car may be in limp mode with reduced power and unpredictable throttle response, which can be unsafe in traffic. Drive only short distances if you must, and get it fixed soon.

Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.