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Test J: No Universal Asynchronous Receiver-Transmitter (UART)-Based Protocol (UBP) Network Communication

PINPOINT TEST J: NO UNIVERSAL ASYNCHRONOUS RECEIVER-TRANSMITTER (UART)-BASED PROTOCOL (UBP) NETWORK COMMUNICATION


J1:






J1-J5:






J5-J11:






J11-J14:






J15:






Normal Operation
The UBP network is comprised of the driver seat module (DSM) (if equipped), the electronic automatic temperature control (EATC) module (if equipped), the vehicle security module (VSM) (if equipped) and the instrument cluster. All modules communicate with the scan tool through the UBP communications network circuit 1906 (VT).

Possible Causes
- Circuit 1906 (VT) open, short to ground or voltage
- VSM
- DSM
- EATC module
- Instrument cluster