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DTC P1718 CAN COMMUNICATION CIRCUIT

DTC P1718 CAN COMMUNICATION CIRCUIT

DIAGNOSIS:

Input signal circuit of TCM is open or shorted.

WIRING DIAGRAM:


CHECK DTC.

Check if multiple trouble codes appear in the on-board diagnostics test mode.

Are multiple DTCs displayed?

Yes

Go to other DTC.


No


CHECK HARNESS CONNECTOR BETWEEN TCM AND ECM.

Turn the ignition switch to OFF.

Disconnect TCM and ECM connectors.

Measure resistance of harness between ECM and TCM connector.

Connector & Terminal

(B55) No. 3 — (B137) No. 18:

Is the measured value less than 1 Ω?

Yes


No

Repair open circuit in harness between TCM and ECM, or poor contact in coupling connector.


CHECK HARNESS CONNECTOR BETWEEN TCM AND ECM.

Measure resistance of harness between ECM and TCM connector.

Connector & Terminal

(B55) No. 12 — (B137) No. 26:

Is the measured value less than 1 Ω?

Yes


No

Repair open circuit in harness between TCM and ECM, or poor contact in coupling connector.


CHECK HARNESS CONNECTOR BETWEEN TCM AND ECM.

Measure resistance of harness between TCM and chassis ground.

Connector & Terminal

(B55) No. 3 — Chassis ground:

(B55) No. 12 — Chassis ground:

Is the measured value more than 1 MΩ?

Yes

There is failure in the TCM or ECM. (Replace and check again)


No

Repair short circuit in harness between TCM and ECM.