Pinpoint Test W: No Power To The Scan Tool

Communications Network

Pinpoint Test W: No Power To The Scan Tool

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

Normal Operation

The scan tool is connected to the Data Link Connector (DLC) to communicate with the High Speed Controller Area Network (HS-CAN) and Medium Speed Controller Area Network (MS-CAN).

A loss of ground or poor ground at the DLC (Data Link Connector) may result in HS-CAN (High Speed Controller Area Network) or MS-CAN (Medium Speed Controller Area Network) faults while the scan tool is connected.

This pinpoint test is intended to diagnose the following:

- Fuse

- Wiring, terminals or connectors

- DLC (Data Link Connector)

- Scan tool

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 Inspection and Verification.

NOTE: Failure to disconnect the battery when instructed will result in false resistance readings.

W1 CHECK DLC (Data Link Connector) PINS FOR DAMAGE

- Disconnect the scan tool cable from the DLC (Data Link Connector).

- Inspect the DLC (Data Link Connector) pins 4, 5 and 16 for damage.





Are the DLC (Data Link Connector) pins 4, 5 and 16 OK?

Yes
GO to W2.

No
REPAIR the DLC (Data Link Connector) as necessary. REPEAT the network test with the scan tool.

W2 CHECK THE DLC (Data Link Connector) VOLTAGE SUPPLY CIRCUIT FOR AN OPEN

- Measure the voltage between the DLC (Data Link Connector) 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. If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short Electrical Diagrams. REPEAT the network test with the scan tool.

W3 CHECK THE DLC (Data Link Connector) GROUND CIRCUITS FOR AN OPEN

- Disconnect: Negative Battery Cable.

- Measure the resistance between the DLC (Data Link Connector) C251-4, circuit GD112 (BK/GN), harness side and ground; and between the DLC (Data Link Connector) C251-5, circuit GD114 (BK/BU), harness side and ground.





Are the resistances less than 5 ohms?

Yes
REPAIR the scan tool. CONNECT the negative battery cable. REPEAT the network test with the scan tool.

No
REPAIR the circuit in question. CONNECT the negative battery cable. REPEAT the network test with the scan tool.