P0122 — Throttle Position Sensor/Switch A Circuit Low Input
Category: Powertrain Severity: High
Updated:
DTC code P0122 means: Throttle Position Sensor/Switch A Circuit Low Input. It falls under the "Powertrain" category, with an estimated severity of High. Common causes include failed TPS, signal wire shorted to ground or open and missing 5 V reference; it's worth confirming the diagnosis before replacing parts.
Possible causes
- Failed TPS
- Signal wire shorted to ground or open
- Missing 5 V reference
- Loose connector
Symptoms
- Limp mode
- No acceleration
- High or unstable idle
- Check engine light
How to diagnose it step by step
- Check the connector.
- Measure the 5 V reference.
- Measure signal at rest and wide open.
- Replace the sensor or throttle body.
How to fix it
Measure the 5 V reference and signal (about 0.5 V at rest). If 5 V is missing, the fault is in the wiring or another sensor sharing the reference.
Estimated repair cost
$40–600 depending on whether the sensor is integrated.
Frequently asked questions
What does DTC code P0122 mean?
Throttle Position Sensor/Switch A Circuit Low Input.
Is code P0122 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 P0122?
Only as needed; power will be heavily limited.
Related codes
P0121 P0123 P0120 P0125 P0128 P0118 P0117 P0116 P0115 P0130
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