Pinpoint Test P: No Power To The Scan Tool

Communications Network

Pinpoint Test P: No Power To The Scan Tool

Refer to Wiring Diagrams 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 P : 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.

P1 CHECK THE DLC (Data Link Connector) PINS FOR DAMAGE

- Ignition OFF.

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

Yes
GO to P2.

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

P2 CHECK THE VOLTAGE TO THE SCAN TOOL VOLTAGE SUPPLY CIRCUIT FOR AN OPEN

- Measure the voltage between the DLC (Data Link Connector) C251-16, circuit 30-RA1 (RD), harness side and ground.





Is the voltage greater than 10 volts?

Yes
GO to P3.

No
VERIFY the Battery Junction Box (BJB) fuse 6 (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. REPEAT the network test with the scan tool. Electrical Diagrams

P3 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 31-RA1 (BK), harness side and ground; and between the DLC (Data Link Connector) C251-5, circuit 91-RA1 (BK/OG), 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.