P0123

TORQDEX // POWERTRAIN DTC

Throttle / Pedal Position Sensor Circuit High Input

The throttle or accelerator position sensor signal is above the expected electrical range.

CODE FAMILY Powertrain
SEVERITY HIGH
DRIVEABILITY DRIVEABILITY MAY BE LIMITED
COMMON AREA Throttle Position / Pedal Sensor / Wiring

00 // CODE DEFINITION

What P0123 means

P0123 means a throttle or accelerator position signal is higher than the expected operating range.

A sensor failure, short to voltage, connector problem, or reference circuit fault may trigger the code.

01 // COMMON SYMPTOMS

What you may notice

Reduced engine power
Poor throttle response
Check-engine light
High or unstable idle
Possible limp mode

02 // COMMON CAUSES

What can trigger P0123?

SENSOR

Position sensor fault

An internal sensor problem can create an excessively high output.

WIRING

Signal short to voltage

Harness damage may force the signal above its expected range.

CONNECTOR

Terminal problem

Corrosion or poor pin contact can interfere with position readings.

03 // DRIVEABILITY

Can I keep driving with P0123?

SEVERITY HIGH
DRIVEABILITY MAY BE LIMITED

Use caution. A high-severity fault can affect engine, transmission, electrical, or emissions-system operation. If the vehicle is running poorly, overheating, losing oil pressure, flashing the check-engine light, or entering reduced-power mode, avoid continued driving until the cause is diagnosed.

04 // DIAGNOSTIC ORDER

Start here

01

Check live throttle data

Look for an implausibly high or fixed position reading.

02

Inspect the harness

Check for damaged insulation, loose connectors, or terminal issues.

03

Measure circuit voltages

Verify reference, ground, and signal circuits.

04

Compare redundant sensors

On electronic throttle systems, compare related position signals for proper correlation.

05 // COMMON REPAIR AREAS

Systems commonly involved

These are common areas associated with P0123. Testing should confirm the actual fault before parts are replaced.

SENSOR

Position sensor fault

An internal sensor problem can create an excessively high output.

WIRING

Signal short to voltage

Harness damage may force the signal above its expected range.

CONNECTOR

Terminal problem

Corrosion or poor pin contact can interfere with position readings.

06 // DIAGNOSTIC PRINCIPLE

Confirm the fault before replacing parts

P0123 identifies a condition detected by the vehicle control system. It does not automatically identify one failed component. Test the affected system before replacing parts.

07 // RELATED TORQDEX DIAGNOSTICS

Related diagnostic guides

Continue troubleshooting by symptom and system. These TorqDex guides cover common diagnostic paths associated with this trouble code.

08 // RELATED CODES

Related trouble codes