No Comm from Any Board to Main Micro
system
Description
Main microprocessor cannot communicate with any modules over the CAN bus, and the unit issues a required shutdown.
Activation Conditions
Main microprocessor cannot communicate with any modules over the CAN bus.
Unit Behavior
Engine and Electric Operation: Required Shutdown. If alarm remains active for 2 minutes issue a shutdown command to all modules except the display.
Reset Conditions
Auto reset when CAN communication is restored, or alarm may be manually reset by turning the unit off, then back on again.
Corrective Actions
1. Check CAN bus a. Inspect connector pins and terminals - CAN Hi: PM-23 to 1-1MSM-12, 1-1MSM-2 to 1-2MSM- 29, 1-2MSM-27 to ENCU-23 and ES-D, ES-H to CCB-5. CAN Lo: PM-12 to 1-1MSM-3, 1- 1MSM-6 to 1-2MSM-30, 1-2MSM-28 to ENCU-24 and ES-C, ES-G to CCB-17. Verify no damage or corrosion in connections. b. Check for CAN circuit continuity: CAN Hi; Refer to Section 4.2 CAN Lo; Refer to Section 4.2. If good continuity not present, check connectors and wiring between terminals for damage, moisture or corrosion. 2. Check for other CAN bus alarms - This alarm may accompany by other alarms, complete troubleshooting steps for alarms found. If repairs have been made and the other alarms have cleared, further troubleshooting may not be required. If this alarm reoccurs, check CAN bus as described in the proceeding step. 3. Perform and analyze a data download