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Pinpoint Test Q: The Power Running Board (PRB) Module Does Not Respond To The Scan Tool




Communications Network

Pinpoint Test Q: The Power Running Board (PRB) Module Does Not Respond To The Scan Tool

Normal Operation

The Power Running Board (PRB) module communicates with the scan tool through the Medium Speed Controller Area Network (MS-CAN). Circuits VDB06 (GY/OG) (MS-CAN +) and VDB07 (VT/OG) (MS-CAN -) provide the network connection to the PRB module. Voltage for the PRB module is provided by circuit SBB11 (BU/RD). Circuit GD134 (BK/VT) provides ground.

This pinpoint test is intended to diagnose the following:

- Fuse
- Wiring, terminals or connectors
- PRB module



PINPOINT TEST Q: THE PRB MODULE DOES NOT RESPOND TO THE SCAN TOOL

NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

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

Q1-Q3:





Q3-Q4: