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DTC P0462 FUEL LEVEL SENSOR CIRCUIT LOW INPUT

DTC P0462 FUEL LEVEL SENSOR CIRCUIT LOW INPUT

DTC DETECTING CONDITION:


• Two consecutive driving cycles with fault

• GENERAL DESCRIPTION


Important

After repair or replacement of faulty parts, conduct Clear Memory Mode and Inspection Mode .


WIRING DIAGRAM:


CHECK SPEEDOMETER AND TACHOMETER OPERATION IN COMBINATION METER.

Does the speedometer and tachometer operate normally?

Yes


No

Repair or replace the combination meter.


CHECK INPUT SIGNAL FOR ECM.

Turn the ignition switch to ON. (engine OFF)

Measure the voltage between ECM connector and chassis ground.

Connector & terminal

(B135) No. 25 (+) — Chassis ground (−):

Is the voltage less than 0.12 V?

Yes


No


CHECK INPUT SIGNAL FOR ECM. (USING Vehicle Diagnostic Interface)

Read the data of fuel level sensor signal using Vehicle Diagnostic Interface.

Note
• Vehicle Diagnostic Interface

For detailed operation procedure, refer to the “READ CURRENT DATA FOR ENGINE”.


Does the voltage change, while shaking the ECM harness and connector?

Yes

Repair the poor contact in ECM connector.


No

• Even if malfunction indicator light lights up, the circuit has returned to a normal condition at this time. A temporary poor contact of the connector may be the cause.

•
Note

In this case, repair the following:

• Poor contact in combination meter connector

• Poor contact in ECM connector

• Poor contact in coupling connectors



CHECK INPUT VOLTAGE OF ECM.

Turn the ignition switch to OFF.

Separate the fuel tank cord connector (R57) and rear wiring harness connector (R15).

Turn the ignition switch to ON.

Measure the voltage of harness between ECM connector and chassis ground.

Connector & terminal

(B135) No. 25 (+) — Chassis ground (−):

Is the voltage more than 0.12 V?

Yes


No


CHECK HARNESS BETWEEN ECM AND COMBINATION METER.

Turn the ignition switch to OFF.

Disconnect the connector from connector (i11), (i12) and ECM connector.

Measure the resistance between ECM and chassis ground.

Connector & terminal

(B135) No. 25 — Chassis ground:

Is the resistance more than 1 MΩ?

Yes


No

Repair the ground short circuit in harness between ECM and combination meter connector.


CHECK HARNESS BETWEEN ECM AND COMBINATION METER.

Measure the resistance between ECM and combination meter connector.

Connector & terminal

(B135) No. 25 — (i12) No. 2:

Is the resistance less than 10 Ω?

Yes

Repair or replace the combination meter.


No

• Repair the open circuit between ECM and combination meter connector.

•
Note

In this case, repair the following:

Poor contact in coupling connector



CHECK FUEL TANK CORD.

Turn the ignition switch to OFF.

Disconnect the connector from fuel sub level sensor.

Measure the resistance between fuel sub level sensor and chassis ground.

Connector & terminal

(R59) No. 1 — Chassis ground:

Is the resistance more than 1 MΩ?

Yes


No

Repair the ground short circuit in fuel tank cord.


CHECK FUEL TANK CORD.

Disconnect the connector from fuel pump assembly.

Measure the resistance between fuel pump assembly and chassis ground.

Connector & terminal

(R59) No. 2 — Chassis ground:

Is the resistance more than 1 MΩ?

Yes


No

Repair the ground short circuit in fuel tank cord.


CHECK FUEL LEVEL SENSOR.

Remove the fuel pump assembly.

Measure the resistance between fuel level sensor and terminals with its float set to the full position.

Terminals

No. 2 — No. 3:

Is the resistance 0.5 — 2.5 Ω?

Yes


No

Replace the fuel level sensor.


CHECK FUEL SUB LEVEL SENSOR.

Remove the fuel sub level sensor.

Measure the resistance between fuel sub level sensor and terminals with its float set to the full position.

Terminals

No. 1 — No. 2:

Is the resistance 0.5 — 2.5 Ω?

Yes

Repair the poor contact in harness between ECM and combination meter connector.


No

Replace the fuel sub level sensor.