Code 23, Throttle Position Sensor MISADJUSTED: Notes
WARNING: This page does not describe the selected car, but rather 22 other vehicles, including the 1992 GMC Yukon, 1992 GMC Vandura Special, 1992 GMC Vandura, 1992 GMC Value Van, and 1992 GMC Rally Camper Special. However, it is still accessible from the selected car via links, so may be relevant.
The Throttle Position Sensor (TPS), a variable mechanical resistor, informs ECM of throttle opening. The TPS, connected to a 5-volt reference signal, has a high resistance value at closed throttle. At wide open throttle, TPS resistance is at its lowest, and output to ECM will be close to 5 volts. Code 23 indicates ECM has noted that voltage, at terminal A2, is not .25-1.35 volts for at least 30 seconds, with engine speed at 550-650 RPM.
NOTE:
Test numbers refer to numbers on diagnostic chart.
- This confirms Code 23 fault is present.
- This test determines if sensor signal line is shorted to ground.
- See THROTTLE POSITION SENSOR in N - REMOVE/INSTALL/OHAUL article.