APU IO CAN Fail
system
Description
No APU_IO sync responses were received for 10 seconds, and the unit shuts down and all modules reboot.
Activation Conditions
If Alarm 20001 (CCU CAN Fail) is not active and unit is not starting in diesel, and no sync responses have been received from the APU_IO module for 10 seconds
Unit Behavior
Unit shutdown. All modules will reboot.
Reset Conditions
Sync response received from the APU_IO Module, alarm reset, or power cycle
Corrective Actions
1. Inspect APU Module indicator LED. • Is light solid red • Is light OFF – Power cycle unit from AI if light remains OFF Go to step 2. • If light is blinking green, verify if alarm is still active. If alarm is active inspect harness between APU J1 and CCU J10 2. Inspect alternator, bus bar, and engine B+ and ground connections 3. Inspect APU harness and connector at APU J1 4. Check for 12VDC between APU J1:4 and APU J1:5 5. Check F2 fuse 6. Inspect APU harness and connectors between APU J1 and CCU J10 7. Replace APU Module.