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P0121






DTC P0121
Throttle pot signal inconsistent with MAF, IACV, air temp and engine rpm (Driving Cycle B)

Possible causes by suggested order of priority:
- Connectors C1017, C149.
- Circuit integrity C1017/36 (RB) - C149/3 (RB).
- Circuit integrity C1033/4 (R) - C149/1 (R).
- Circuit integrity C1017/15 (YLG)- C149/2 (YLG).
- Sensor supply from ECM.
- Throttle position sensor.
- ECM.

Connectors C1017, C149.
- Check for connector not correctly latched, backed out pins, damaged pins, corroded pins

Circuit integrity C1017/36 (RB) - C149/3 (RB).
- Check for open circuit, short circuit to ground, supply or other circuit, damaged or unlatched connector, intermediate connectors or headers

Circuit integrity C1033/4 (R) - C149/1 (R).
- Check for open circuit, short circuit to ground, supply or other circuit, damaged or unlatched connector, intermediate connectors or headers

Circuit integrity C1017/15 (YLG)- C149/2 (YLG).
- Check for open circuit, short circuit to ground, supply or other circuit, damaged or unlatched connector, intermediate connectors or headers

Sensor supply from ECM.
- Supply to throttle position sensor from ECM C1033/4 (R).
- Ensure ignition is ON (position 2).
PASS VALUES: Minimum 2.0 Volts.

Throttle position sensor.
- Throttle position sensor resistance.
- Slowly depress the throttle pedal.
- The reading should change smoothly from below 170 ohms to above 900 ohms.

ECM.
- No detail available for this fault