P0121 2002 FORD F150 - Throttle/Pedal Position Sensor/Switch 'A' Circuit Range/Performance
P0121 2002 FORD F150 Possible Causes
- Binding throttle linkage
- Faulty throttle position sensor
- Throttle position sensor harness is open or shorted
- Throttle position sensor circuit poor electrical connection
- Faulty Engine Control Module (ECM)
First diagnose P0121 2002 FORD F150 code
Check the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded terminals.
P0121 2002 FORD F150 Tech NotesThe TP sensor circuit is monitored by the PCM for a non closed throttle position at idle. If key ON engine running self-test terminates upon placing the transmission range selector in gear (DRIVE or REVERSE) or when closing the throttle (idle) after opening it (in PARK or NEUTRAL) the TP closed throttle position is not attained, the test fails.
Cost of diagnosing the P0121 2002 FORD F150 code
Labor: 1.0The cost of diagnosing the P0121 2002 FORD F150 code is 1.0 hour of labor. The auto repair labor rates vary widely across the country, and even within the same city. Most auto repairs shops charge between $75 and $150 per hour.
When is the P0121 2002 FORD F150 code detected?Malfunction is detected when an excessively low or high voltage from the sensor is sent to ECM.
P0121 2002 FORD F150 Possible Symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
P0121 2002 FORD F150 MeaningThe throttle position sensor (TPS) responds to the accelerator pedal movement. This sensor is a kind of potentiometer which transforms the throttle position into output voltage, and emits the voltage signal to the Engine Control Module (ECM). In addition, the sensor detects the opening and closing speed of the throttle valve and feeds the voltage signal to the ECM.
Idle position of the throttle valve is determined by the ECM receiving the signal from the throttle position sensor. This sensor controls engine operation such as fuel cut. On the other hand, the Wide open and closed throttle position switch, which is built into the throttle position sensor unit, is not used for engine control.
P0121 2002 FORD F150 More InformationNeed more information on how to fix the P0121 2002 FORD F150 code?
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