Pinpoint Test W: No Power To The Scan Tool

Communications Network

Pinpoint Tests

Pinpoint Test W: No Power To The Scan Tool

Refer to Wiring Diagram Set 14, Module Communications Network for schematic and connector information. Diagrams By Number

Normal Operation

The scan tool is connected to the Data Link Connector (DLC) to communicate with the High Speed Controller Area Network (HS-CAN), the Medium Speed Controller Area Network (MS-CAN) and the ISO 9141 communications networks. Voltage for the scan tool is provided by circuit SBP20 (GN/RD). Ground is provided by circuits GD115 (BK/GY) and GD113 (BK/YE).

This pinpoint test is intended to diagnose the following:

- Fuse
- Wiring, terminals or connectors
- DLC



PINPOINT TEST W: NO POWER TO THE SCAN TOOL

NOTE: Most faults are due to connector and/or wiring concerns. Carry out a thorough inspection and verification before proceeding with the Pinpoint Test. Failure to disconnect the battery when instructed will result in false resistance readings. Inspection and Verification

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W1 CHECK DLC PINS FOR DAMAGE


- Disconnect the scan tool cable from the DLC.
- Inspect the DLC pins 4, 5 and 16 for damage.




- Are the DLC pins 4, 5 and 16 OK?

Yes
GO to W2.

No
REPAIR the DLC as necessary. CLEAR the DTCs. REPEAT the network test with the scan tool.

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W2 CHECK THE DLC VOLTAGE SUPPLY CIRCUIT FOR AN OPEN


- Measure the voltage between the DLC C251-16, circuit SBP20 (GN/RD), harness side and ground.




- Is the voltage greater than 10 volts?

Yes
GO to W3.

No
VERIFY the Smart Junction Box (SJB) fuse 20 (15A) is OK. If OK, REPAIR the circuit. REPEAT the network test with the scan tool.

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W3 CHECK THE DLC GROUND CIRCUITS FOR AN OPEN


- Measure the resistance between the DLC C251-4, circuit GD115 (BK/GY), harness side and ground; and between the DLC C251-5, circuit GD113 (BK/YE), harness side and ground.




- Are the resistances less than 5 ohms?

Yes
REPAIR the scan tool. REPEAT the network test with the scan tool.

No
REPAIR the circuit in question. REPEAT the network test with the scan tool.

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