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Home >> Geo >> 1993 >> Prizm Base, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes >> DIAGNOSTIC CODE CHARTS (EXCEPT LSi) >> Code 41, TP Sensor Circuit, Open Or Shorted Circuit >> Notes
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Code 41, TP Sensor Circuit, Open Or Shorted Circuit: Notes

Throttle Position (TP) sensor consists of a contact point (idle switch) and a potentiometer, and is connected to throttle valve shaft on throttle body. TP sensor detects throttle valve opening. Idle switch detects throttle opening and turns on during idle. Fully opened throttle is detected by potentiometer.

ECM provides a 5-volt reference voltage to TP sensor and as brush moves over resistance according to throttle valve opening, output voltage varies accordingly. ECM monitors on/off signal and sensor output voltage, and uses these to detect throttle valve opening.

Code 41 will set if throttle position input at ECM indicates Wide Open Throttle (WOT) with engine idling for at least .5 second, or if throttle position input at ECM indicates and idle signal with engine off idle for at least .5 second.

NOTE: Test numbers refer to test numbers on diagnostic chart.
  1. Checks for a fault in Yellow wire between ECM and TP sensor.
  2. Checks for open in Brown wire between ECM and TP sensor.
  3. Checks for a fault in Light Green wire between ECM and TP sensor, a faulty ECM, or a misadjusted or faulty TP sensor.