Code No.21: Lever position sensor system <4M40>

OPERATION

When the accelerator pedal is from the idle position to the fully opened position, the resistance between the lever position sensor output terminal (No.1) and earth terminal (No.3) will increase according.
With the ignition switch in the ON position. Voltage at terminal No.1 increases from approximately 0.5 V to approximately 2.325 V.

DIAGNOSIS CODE SET CONDITIONS

If lever position sensor output voltage is 0.2 V or lower at times other than when the engine is idling, the output is judged to be too low and code No.21 is set.

PROBABLE CAUSES

Malfunction of the lever position sensor circuit
Damaged harness wires and connectors
Malfunction of the transfer-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III data list

Item 1: Lever position sensor (Refer to data list reference table

Q. Is the check result normal?

	Intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).

	Go to Step 2.

STEP 2. Check the lever position sensor.

Refer to GROUP 17 - Emission Control System <4M40>.

Q. Is the check result normal?

	Go to Step 3.

	Repair or replace the fuel injection pump assembly.

STEP 3. Measure the voltage at transfer-ECU connector D-124.

(1)Turn the ignition switch to the ON position.

(2)Measure the voltage between transfer-ECU connector D-124 terminal No.5 and earth.
OK:

0.5 ± 0.05 V (Release the accelerator pedal).

2.325 ± 0.05 V or more (Depress the accelerator pedal fully).

Q. Is the check result normal?

	Go to Step 6.

	Go to Step 4.

STEP 4. Connector check: D-124 transfer-ECU connector, D-225 intermediate connector.

Check for the contact with terminals.

Q. Is the check result normal?

	Go to Step 5.

	Repair the defective connector.

STEP 5. Check the harness between fuel injection pump assembly connector B-134 terminal No.1 and transfer-ECU connector D-124 terminal No.5.

Check the output line for open circuit.

Q. Is the check result normal?

	Go to Step 7.

	Repair the wiring harness.

STEP 6. Connector check: D-124 transfer-ECU connector.

Check for the contact with terminals.

Q. Is the check result normal?

	Go to Step 7.

	Repair the defective connector.

STEP 7. M.U.T.-III data list

Item 1:Lever position sensor (Refer to data list reference table

Q. Is the check result normal?

	Intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).

	Replace the transfer-ECU.