Pinpoint Test Y: No Power To The Scan Tool

Communications Network

Pinpoint Test Y: No Power To The Scan Tool


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 the 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)

PINPOINT TEST Y : 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.

Y1 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 Y2.

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

Y2 CHECK THE DLC (Data Link Connector) VOLTAGE SUPPLY CIRCUIT FOR AN OPEN

- Measure the voltage between the DLC (Data Link Connector) C251-16, circuit SBP24 (VT/RD), harness side and ground.





Is the voltage greater than 10 volts?

Yes
GO to Y3.

No
VERIFY the Body Control Module (BCM) fuse 24 (15A) is OK. If OK, REPAIR the circuit. REPEAT the network test with the scan tool.

Y3 CHECK THE DLC (Data Link Connector) GROUND CIRCUITS FOR AN OPEN

- Measure the resistance between the DLC (Data Link Connector) C251-4, circuit GD115 (BK/GY), harness side and ground; and between the DLC (Data Link Connector) C251-5, circuit GD184 (BK/GY or 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.