GM Code 22 Throttle Position Sensor
CODE 22 - Throttle Position Sensor
Trouble Code 22 indicates that the Throttle Position Sensor (TPS) is reading abnormally low. TPS volts should be close to 0.42 V at closed throttle and rise smoothly in about 0.02 volt increments to a maximum reading of about 4.85 volts at WOT.
The conditions for setting this code are:
- the engine is running, and
- TPS reading is < 0.20 volts
Note: During a Code 22 condition, the ECM uses a default TPS value of 2.6 volts. This will cause the engine to idle very high.
Typical causes for this code include:
1) Maladjusted TPS
2) Defective TPS
3) No +5 volt reference to TPS
4) TPS-return to ECM is shorted to ground or to sensor ground
5) Defective ECM
NOTE: The TPS must be adjusted to about 0.42 volts at closed throttle for the ECM to auto-zero properly. If necessary, adjust the TPS to bring the voltage up or down to this value at closed throttle.
