This is one of the most frequent OBD2 trouble codes. Read the full article below to know what it means, how to fix it, and what other codes may show related to it.
Definition
Throttle Pedal Position Sensor/Switch (TPS) A Circuit Low Input
Meaning
In OBD-II, the P0122 code indicates the Engine Control Module (ECM) has detected a TPS sensor circuit A output voltage that is below the sensor's expected range.
Causes
- The TPS is not securely mounted
- The TPS circuit is shorted to ground or another wire
- Failure of the TPS Damaged computer (PCM)
Symptoms
- Low or rough idle
- Idle is very high
- Surging but stalling
- There is little/no acceleration
Diagnosis
Codes are scanned and documented, and freeze frame data is reviewed to determine when the code was set
Tests to see if the OBD-II fault code reappears after clearing the fault codes
Check for damaged or loose connections on all TPS units
Comparison of TPS circuits A and B is done on the scanner and if there is a problem, the manufacturer's recommended TPS pinpoint tests are performed
Performs a road test after replacing the TPS, clearing the codes, and replacing the TPS if needed
Common mistakes
Insufficiently checking for damage visually
Failure to scan, document, clear and retest the codes in order to verify failures
A TPS sensor was replaced without any indication that it was problematic
By not comparing the TPS sensor A and B before and after repair or replacement
How serious is this?
The P0122 code causes your engine's ECM to enter a failsafe mode, which may cause your engine to stall, buck or jerk, lack acceleration, or exhibit high idle speeds, depending on the failsafe mode settings used by the manufacturer.
What repairs can fix the code?
The throttle position sensor (TPS), wiring connectors, and other components should be examined carefully for breaks, etc. Replace or repair as needed.
(See your vehicle's service manual for more information). Too low a voltage is a sign that something is wrong. You may need to replace it.
A TPS adjustment may be necessary if it was recently replaced. A repair manual will detail how to adjust or align the TPS on certain vehicles.
When there is no symptom, the code can be cleared if the problem is intermittent. It is important that you check the wiring to make sure it is not rubbing on anything or grounded incorrectly. It is possible for the code to return
Related codes
None listed.
Conclusion
If your car is experiencing any of the symptoms listed above, you may have a P0122 code. Your best bet is to schedule an appointment with your mechanic.
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