OBD codes / P0122
P0122
SeriousThrottle/Pedal Position Sensor A Circuit Low
Take P0122 a bit more seriously than most sensor codes — it can put the car into reduced-power mode and cause poor or unpredictable throttle response, which is a safety consideration in traffic. It's usually drivable to a shop, but get it diagnosed promptly and avoid relying on the car if throttle response feels off.
What this code means
The throttle position sensor (TPS) tells the computer how far the throttle is open so it can deliver the right fuel and, on drive-by-wire cars, control the throttle itself. P0122 means that sensor's signal is reading too low (or shorted to ground). Common causes are a failed sensor, a wire shorted to ground, or a corroded connector. On modern electronic throttle bodies the TPS is built in, so the fix may be the whole throttle body. Because the computer relies on this for throttle control, a fault can drop the car into a reduced-power "limp" mode.
Symptoms you might notice
- Hesitation, surging, or poor throttle response
- Reduced-power or "limp" mode
- Stalling or rough idle
- Unexpected shifts on automatics
- Check-engine light, sometimes with a warning light
What it costs to fix
Typical range: $50–$500 · about ~0.3–1.5 hrs of labor
| If the cause is… | Part | Labor |
|---|---|---|
| Throttle position sensor (standalone) | $20–$100 | ~0.3–0.8 hrs |
| Electronic throttle body (integrated TPS) | $150–$500 | ~0.5–1.5 hrs |
| Wiring / connector repair | $10–$120 | ~0.5–1.5 hrs |
On older cars with a bolt-on TPS it's a cheap fix; on newer drive-by-wire cars the sensor is part of the throttle body, which is the expensive end. A wiring or connector repair is inexpensive once found.
The price swings on which cause it turns out to be — so confirm the cause before paying. Diagnose P0122 for my exact vehicle →
Frequently asked
Can I drive with P0122?
Cautiously and not for long. It can cause hesitation or drop the car into reduced-power mode, which is risky in traffic. Driving gently to a shop is usually fine, but don't ignore it if throttle response is unpredictable.
Will P0122 cause limp mode?
It can. Because the computer depends on the throttle signal, a fault often triggers a reduced-power "limp" mode as a safety fallback — the car runs but acceleration is limited until it's fixed.
Is the TPS part of the throttle body?
On most modern drive-by-wire vehicles, yes — the throttle position sensor is integrated into the electronic throttle body, so the repair may mean the whole unit. Older cars often have a separate, cheaper bolt-on sensor.
How much does it cost to fix P0122?
Cheap on older cars with a standalone sensor; more on newer ones where it means a throttle body. Wiring/connector fixes are inexpensive. Diagnosis tells you which applies before you buy parts.
Seeing P0122 on your car? Get a diagnosis specific to your exact year, make and model.
Diagnose P0122 for my vehicleGeneric OBD-II reference. Manufacturer-specific behavior varies — confirm with a scan tool and, for safety-related codes, a professional inspection.