P0123 — Throttle Position Sensor/Switch A Circuit High Input
Category: Powertrain Severity: High
Updated:
DTC code P0123 means: Throttle Position Sensor/Switch A Circuit High Input. It falls under the "Powertrain" category, with an estimated severity of High. Common causes include failed TPS, signal wire shorted to 5 V or 12 V and open sensor ground; it's worth confirming the diagnosis before replacing parts.
Possible causes
- Failed TPS
- Signal wire shorted to 5 V or 12 V
- Open sensor ground
- Damaged connector
Symptoms
- Limp mode
- High idle
- Erratic acceleration
- Check engine light
How to diagnose it step by step
- Measure the sensor ground.
- Check the wiring.
- Measure the signal.
- Replace the part.
How to fix it
Check the sensor ground: an open ground drives the signal high. If the ground is good, replace the sensor or throttle body.
Estimated repair cost
$40–600.
Frequently asked questions
What does DTC code P0123 mean?
Throttle Position Sensor/Switch A Circuit High Input.
Is code P0123 serious?
Severity High. Have it checked as soon as possible, especially if it affects safety or the catalytic converter.
Can I keep driving with code P0123?
Only as needed.
Related codes
P0122 P0121 P0125 P0120 P0128 P0118 P0117 P0116 P0130 P0115
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