DTC P0120/41 Throttle Pedal Position Sensor / Switch "A" Circuit Malfunction |
DTC P0122/41 Throttle / Pedal Position Sensor / Switch "A" Circuit Low Input |
DTC P0123/41 Throttle / Pedal Position Sensor / Switch "A" Circuit High Input |

| DTC No. | DTC Detection Condition | Trouble Area |
| - | Condition of DTC P0120/41, P0122/41 or P0123/41 continues for 5 seconds (open or short in throttle position sensor circuit) | - |
| P0120/41 | Throttle position sensor output (VLU) flutters up and down beyond normal operating range (less than 0.2 V or more than 4.8 V) (1 trip detection logic) |
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| P0122/41 | Throttle position sensor output (VLU) is less than 0.2 V (1 trip detection logic) |
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| P0123/41 | Throttle position sensor output (VLU) is more than 4.8 V (1 trip detection logic) |
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| 1.CHECK WIRE HARNESS (THROTTLE POSITION SENSOR - ECM) |
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Disconnect the E7 and E8 ECM connectors.
Disconnect the T2 throttle position sensor connectors.
Measure the resistance of the wire harness side connectors.
| Tester Connection | Specified Condition |
| E8-18 (VC) - T2-1 (VC) | Below 1 Ω |
| E7-29 (VLU) - T2-3 (VTA) | Below 1 Ω |
| E8-28 (E2) - T2-2 (E2) | Below 1 Ω |
| E8-18 (VC) or T2-1 (VC) - Body ground | 10 kΩ or higher |
| E7-29 (VLU) or T2-3 (VTA) - Body ground | 10 kΩ or higher |
| E8-28 (E2) or T2-2 (E2) - Body ground | 10 kΩ or higher |
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| OK | |
| 2.CHECK ECM (VC VOLTAGE) |
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Disconnect the T2 throttle position sensor connectors.
Turn the ignition switch ON.
Measure the voltage of the ECM connector.
| Tester Connection | Specified Condition |
| E8-18 (VC) - E8-28 (E2) | 4.5 to 5.5 V |
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| OK | |
| 3.REPLACE DIESEL THROTTLE BODY (THROTTLE VALVE) |
| NEXT | |
| 4.CHECK IF DTC OUTPUT RECURS (DTC P0120/41, P0122/41 AND/OR P0123/41) |
Clear the DTC(s) (Click here).
Start the engine.
Idle the engine for 60 seconds, and repeat quick engine revving to 2,500 rpm for 30 seconds.
Read the DTC(s).
| Display (DTC Output) | Proceed to |
| P0120/41, P0122/41 and/or P0123/41 | A |
| No output | B |
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| A | ||
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