Pinpoint Test A: The PCM Does Not Respond To The Scan Tool

Communications Network


Pinpoint Test A: The PCM Does Not Respond To The Scan Tool

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

Refer to Wiring Diagram Set 23, Electronic Engine Controls - 4.6L for schematic and connector information. Diagrams By Number

Refer to Wiring Diagram Set 24, Electronic Engine Controls - 5.4L for schematic and connector information. Diagrams By Number

Normal Operation

The PCM communicates with the scan tool through the High Speed Controller Area Network (HS-CAN). Circuits VDB04 (WH/BU) (HS-CAN +) and VDB05 (WH) (HS-CAN -) provide the network connection to the PCM. An Integrated Diagnostic System (IDS) session cannot be established if PCM communication fails when attempting to identify the vehicle.

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors
- PCM



PINPOINT TEST A: THE PCM 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.

A1-A4:

A4-A5: