ENGINE (DIAGNOSTICS)(H4DOTC DIESEL) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)

DTC P2127 THROTTLE/PEDAL POSITION SENSOR/SWITCH “E” CIRCUIT LOW INPUT

DTC DETECTING CONDITION:

Immediately at fault recognition

TROUBLE SYMPTOM:

Improper idling

Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode and Inspection Mode .

WIRING DIAGRAM:

STEPCHECKYESNO

1.CHECK ACCELERATOR PEDAL POSITION SENSOR POWER SUPPLY.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the accelerator pedal position sensor.

3) Turn the ignition switch to ON.

4) Measure the voltage between accelerator pedal position sensor and chassis ground.

Connector & terminal

(B315) No. 1 (+) — Chassis ground (−):

Is the voltage 4.5 V or more?

Repair the harness and connector.

NOTE:

In this case, repair the following item:

Open circuit of harness between ECM connector and accelerator pedal position sensor connector.

Poor contact of ECM connector

Poor contact of coupling connector

2.CHECK HARNESS BETWEEN ECM AND ACCELERATOR PEDAL POSITION SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance of harness between ECM connector and accelerator pedal position sensor connector.

Connector & terminal

(B135) No. 28 — (B315) No. 3:

Is the resistance less than 1 Ω?

Repair the open circuit of harness between ECM connector and accelerator pedal position sensor connector.

3.CHECK HARNESS BETWEEN ECM AND ACCELERATOR PEDAL POSITION SENSOR.

Measure the resistance between ECM connector and chassis ground.

Connector & terminal

(B135) No. 28 — Chassis ground:

Is the resistance 1 MΩ or more?

Repair the short circuit to ground in harness between ECM connector and accelerator pedal position sensor connector.

4.CHECK SHORT CIRCUIT INSIDE THE ECM.

1) Connect the connector to ECM.

2) Measure the resistance between accelerator pedal position sensor connector and chassis ground.

Connector & terminal

(B315) No. 3 — Chassis ground:

Is the resistance 10 kΩ or more?

Replace the accelerator pedal.

Repair the short circuit to ground in harness between ECM connector and accelerator pedal position sensor connector. Replace the ECM if defective.