Code No. P2138: Accelerator Pedal Position Sensor (main and sub) Range/Performance Problem

OPERATION

Check code No. P2122: accelerator pedal position sensor (main) circuit low input (Refer to ).
Check code No. P2127: accelerator pedal position sensor (sub) circuit low input (Refer to ).

FUNCTION

Engine-ECU checks the accelerator pedal position sensor output signal characteristics for abnormal conditions.

TROUBLE JUDGEMENT

Check Conditions

Ignition switch is "ON" position.
Change of accelerator pedal position sensor (sub) output voltage per 25 milliseconds is less than 0.06 V.

Judgement Criterion

Voltage obtained with the formula given below is more than 0.39 V for 0.3 second: [accelerator pedal position sensor (sub) output voltage +0.3 V - accelerator pedal position sensor (main) output voltage].

Check Conditions

Ignition switch is "ON" position.
Change of accelerator pedal position sensor (sub) output voltage per 25 milliseconds is less than 0.06 V.

Judgement Criterion

Voltage obtained with the formula given below is more than 0.39 V for 0.2 second: [accelerator pedal position sensor (main) output voltage - accelerator pedal position sensor (sub) output voltage].

FAIL-SAFE AND BACKUP FUNCTIONS

Throttle opening degree is restricted.
Throttle opening degree position is in default position if accelerator pedal position sensor (sub) fails.

PROBABLE CAUSES

Failed accelerator pedal position sensor
Harness damage in accelerator pedal position sensor circuit or loose connector contact
Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. Check of harness damage in APS5 line between accelerator pedal position sensor connector and engine-ECU connector.

Q. Is the check result normal?

	Go to Step 2.

	Repair the connector(s) or wiring harness.

STEP 2. Check of harness damage in APSM line between accelerator pedal position sensor connector and engine-ECU connector.

Q. Is the check result normal?

	Go to Step 3.

	Repair the connector(s) or wiring harness.

STEP 3. Check of harness damage in APSE line between accelerator pedal position sensor connector and engine-ECU connector.

Q. Is the check result normal?

	Go to Step 4.

	Repair the connector(s) or wiring harness.

STEP 4. Check of harness damage in AP5 line between accelerator pedal position sensor connector and engine-ECU connector.

Q. Is the check result normal?

	Go to Step 5.

	Repair the connector(s) or wiring harness.

STEP 5. Check of harness damage in APSS line between accelerator pedal position sensor connector and engine-ECU connector.

Q. Is the check result normal?

	Go to Step 6.

	Repair the connector(s) or wiring harness.

STEP 6. Check of harness damage in APE line between accelerator pedal position sensor connector and engine-ECU connector.

Q. Is the check result normal?

	Go to Step 7.

	Repair the connector(s) or wiring harness.

STEP 7. Replace the accelerator pedal assembly

After replacing the accelerator pedal assembly, reconfirm whether the diagnosis code is set.

Q. Is diagnosis code set?

	Replace the engine-ECU.

	Check end.