ENGINE (DIAGNOSTICS)(H4DOTC DIESEL) > Diagnostics for Engine Starting Failure

FUEL INJECTOR CIRCUIT

CAUTION:

• Check or repair only faulty parts.

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

WIRING DIAGRAM:

STEPCHECKYESNO

1.CHECK HARNESS BETWEEN ECM AND FUEL INJECTOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and all fuel injectors.

3) Measure the resistance of harness between ECM connector and fuel injector connector.

Connector & terminal

#1 (B134) No. 21 — (E5) No. 1:

#1 (B134) No. 39 — (E5) No. 2:

#1 (B134) No. 40 — (E5) No. 2:

#2 (B134) No. 21 — (E16) No. 1:

#2 (B134) No. 37 — (E16) No. 2:

#2 (B134) No. 38 — (E16) No. 2:

#3 (B134) No. 20 — (E6) No. 1:

#3 (B134) No. 18 — (E6) No. 2:

#3 (B134) No. 19 — (E6) No. 2:

#4 (B134) No. 20 — (E17) No. 1:

#4 (B134) No. 16 — (E17) No. 2:

#4 (B134) No. 17 — (E17) No. 2:

Is the resistance less than 1 Ω?

Repair the harness and connector.

NOTE:

In this case, repair the following item:

• Open circuit in harness between ECM connector and fuel injector connector

• Poor contact of coupling connector

2.CHECK HARNESS BETWEEN ECM AND FUEL INJECTOR CONNECTOR.

Measure the resistance between ECM connector and chassis ground and the resistance in ECM connector.

Connector & terminal

#1 (B134) No. 21 — Chassis ground:

#1 (B134) No. 39 — Chassis ground:

#1 (B134) No. 40 — Chassis ground:

#1 (B134) No. 21 — (B134) No. 65:

#1 (B134) No. 39 — (B134) No. 65:

#1 (B134) No. 40 — (B134) No. 65:

#2 (B134) No. 21 — Chassis ground:

#2 (B134) No. 37 — Chassis ground:

#2 (B134) No. 38 — Chassis ground:

#2 (B134) No. 21 — (B134) No. 65:

#2 (B134) No. 37 — (B134) No. 65:

#2 (B134) No. 38 — (B134) No. 65:

#3 (B134) No. 20 — Chassis ground:

#3 (B134) No. 18 — Chassis ground:

#3 (B134) No. 19 — Chassis ground:

#3 (B134) No. 20 — (B134) No. 65:

#3 (B134) No. 18 — (B134) No. 65:

#3 (B134) No. 19 — (B134) No. 65:

#4 (B134) No. 20 — Chassis ground:

#4 (B134) No. 16 — Chassis ground:

#4 (B134) No. 17 — Chassis ground:

#4 (B134) No. 20 — (B134) No. 65:

#4 (B134) No. 16 — (B134) No. 65:

#4 (B134) No. 17 — (B134) No. 65:

Is the resistance 1 MΩ or more?

Repair the short circuit to ground in harness between ECM connector and fuel injector connector.

3.CHECK POOR CONTACT.

Check for poor contact of ECM connector and fuel injector connector.

Is there poor contact of ECM connector or fuel injector connector?

Repair the poor contact of the ECM connector or fuel injector connector.

4.CHECK FUEL INJECTOR.

Measure the resistance between each fuel injector terminals.

Terminals

No. 1 — No. 2:

Is the resistance 0.2 — 1 Ω?

Check glow plug circuit.

Replace the faulty fuel injector.