Fault code P0122 is called “Throttle Position Sensor/Switch (TPS) “A” Circuit Low Input” but in different programs it may be called differently. This fault designation applies to all vehicles equipped with OBD-II.
Technical description and explained code P0122
This Diagnostic Trouble Code (DTC) is a generic powertrain code. Error P0122 is considered a general code because it applies to all makes and models of vehicles. Although the specific repair steps may vary slightly depending on the model.
The throttle position sensor (TPS) reacts to the movement of the accelerator pedal. It is a type of potentiometer. It converts the throttle position into a voltage output and sends a voltage signal to the engine control module (ECM). It also determines the opening and closing speed of the throttle and provides a voltage signal to the ECM.
Code P0122 means the vehicle’s computer has detected that the Throttle Position Sensor (TPS) “A” is reporting too low a voltage. On some vehicles, this lower limit is 0.17-0.20 volts (V).
Simply put, the throttle position sensor is used to determine which position the throttle is in. If the signal value is less than 0.17V, the PCM sets this code.
Symptoms of vehicle malfunctions
The main signal that an error P0122 has occurred is the Malfunction Indicator Lamp (MIL) is also known as the CheckEngine Light.
It can also be warning signs such as:
- Check engine light on the control panel will illuminate.
- Unstable or low idle speed.
- Increased engine rpm at idle speed.
- The engine stalls or starts poorly.
- The engine is irregular (pulsating).
- No reaction on gas pedal.
- Other symptoms may also be present.
When fault P0122 appears, the engine may run at higher idle speed, but the vehicle will not accelerate properly. The vehicle engine may also run erratically or suddenly stall. This fault can cause a number of problems that will be present until the error is corrected.
Factors that can cause this error code
The error code P0122 can mean that one or more of the following problems have occurred:
- Throttle position sensor circuit is open or bad electrical connection.
- Throttle position sensor wiring harness is open or shorted to ground or other wire.
- Throttle position sensor is defective.
- Damaged computer (PCM).
How to fix or reset OBD-2 code P0122
Some suggested steps for troubleshooting and fix the error code P0122:
- Read all stored data and error codes with an OBD-II scan tool. To find out when and under what circumstances the error occurred.
- Clear the error codes from the computer memory and test-drive the vehicle to find out if the malfunction appears again.
- Visually inspect the electrical wiring and connections related to the throttle “A” position sensor for looseness and damage.
- Compare “A” and “B” throttle position sensors using a scan tool, and replace faulty sensor if necessary.
- Clear error code from computer memory again, test drive vehicle to see if problem is resolved.
Diagnose and repair of problems
Throttle position sensor (TPS), wiring harness connector, and wiring for breaks, etc. Repair or replace if necessary to clear error P0122.
Check the voltage at the TPS (refer to your vehicle’s service manual for more information). If the voltage is too low, this indicates a problem. Replace the sensor if necessary.
If recently replaced, you may need to adjust the TPS. On some vehicles, the installation instructions require a proper adjustment (see repair manual for details).
If there are no symptoms, the problem may be intermittent, and clearing the code may temporarily resolve it. If this is the case, you should definitely check the wiring to make sure it is not rubbing or frayed anywhere, etc.
Other fault codes related to the TPS sensor and circuit: P0120, P0121, P0123, P0124.
On which vehicles does this problem occur most frequently
Fault code P0122 can occur on different vehicles but there are statistics on which brands this occurs most often. Here is a list of some of them:
- Chery
- Chevrolet (Aveo, Cruze, Impala, Lacetti, Lanos, Malibu, Silverado, Spark, Traverse)
- Chrysler
- Citroen (Berlingo)
- Daewoo (Leganza, Matiz, Nexia)
- Dodge (RAM)
- Ford (Focus, Galaxy, Mondeo, Transit)
- Geely (Emgrand)
- Honda (Accord, Civic, Fit, Jazz)
- Hover
- Hyundai (Santa Fe, Solaris, Sonata)
- Jeep (Liberty)
- Kia (Magentis, Rio, Sorento)
- Lifan (Solano)
- Mazda
- Mercedes-Benz
- Mitsubishi (Colt, Lancer)
- Nissan
- Opel (Astra)
- Peugeot (206, 307, 308, Partner)
- Skoda (Fabia, Yeti) (Crosstrek, Forester, Impreza, Legacy, Outback, SVX, Tribeca, XV)
- Subaru
- Suzuki
- Toyota (Corolla)
- Volkswagen (Crafter, Golf, Jetta, Passat, Polo, Tiguan)
- GAZelle (Business, UMZ 4216)
- LADA (Granta, Kalina, Niva, Priora)
- UAZ (Buhanka, Patriot)
- VAZ (2107, 2109, 2110, 2112, 2114, 2115)
- ZAZ (Chance)
Fault code P0122 can sometimes be found with other errors. The most common are the following: P0102, P0108, P0113, P0118, P0222, P0223, P0300, P0335, P0341, P0343, P0452, P0463, P0719, P1122, P1381, P1403, P1961, P2135, C0242, U2100.
