Test M: The Digital Signal Processing Module Does Not Respond To The Diagnostic Tool

PINPOINT TEST M: THE DIGITAL SIGNAL PROCESSING MODULE DOES NOT RESPOND TO THE DIAGNOSTIC TOOL

M1:

M2-M3:

Normal Operation
The digital signal processing module communicates with the diagnostic tool through the medium speed controller area network (CAN), circuits VDB06 (GY/OG) and VDB07 (VT/OG).

Check the medium speed CAN circuits VDB06 (GY/OG) and VDB07 (VT/OG) between the digital signal processing module C4326a and the data link connector (DLC) C251. The total resistance values must not be more than 5 ohms. If the resistance is more than 5 ohms there is an open in one of the high speed CAN circuits, damage to the DLC C251, damage to the digital signal processing module C4326a, or a problem in an in-line connector.

Possible Causes
- medium speed CAN data plus circuit VDB06 (GY/OG) open
- medium speed CAN data minus circuit VDB07 (VT/OG) open
- digital signal processing module C4326a
- digital signal processing module