Pinpoint Test 17: Intermittent No Medium Speed Controller Area Network (MS-CAN) Communication, Communication CAN Be Intermitten
PINPOINT TEST 17: INTERMITTENT NO MEDIUM SPEED CONTROLLER AREA NETWORK (MS-CAN) COMMUNICATION, COMMUNICATION CAN BE INTERMITTENTLY ESTABLISHED
Normal Operation
The Medium-Speed Controller Area Network (MS-CAN) uses an unshielded twisted pair cable. Circuits (GY/O) and (P/O) provide the network connection to all modules on the network. In the event that 1 of the 2 network circuits (MS-CAN + or MS-CAN -) becomes open to a module on the network, unreliable network communication to all modules on the network may result.
Possible Causes
- Audio Control Module (ACM)
- Accessory Protocol Interface Module (APIM)
- Front Controls Interface Module (FCIM)
- Front Display Interface Module (FDIM)
- HVAC module
- Instrument Cluster (IC)
- Satellite Digital Audio Receiver System (SDARS) module
- Smart Junction Box (SJB)
Diagnostic Procedure
CAUTION:Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
NOTE:Most faults are due to connector and/or wiring concerns. Carry out a thorough inspection and verification before proceeding with the Pinpoint Test.
NOTE:Failure to disconnect the battery when instructed will result in false resistance readings. See Battery Disconnect.
