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26100
NO COMM FROM MICRO TO ENCU
• ACTIVATION: Main microprocessor cannot communicate with the engine control unit over the CAN bus.
• UNIT CONTROL: Shutdown and alarm.
• RESET CONDITION: Auto reset when CAN communication is restored, alarm reset or alarm may be man-
ually reset by turning the unit off, then back on again.
NOTE: Follow the steps below until a problem is found. Once a repair or correction has been made, clear the
alarm(s). (Refer to Note 1 in
Section, page 7-2.) Operate the unit through the appropriate modes to see if
any active alarm occurs. Continue with the steps below as necessary.
CORRECTIVE ACTIONS:
1.
Check Both Active and Inactive Alarms for other “ NO COMM” Alarms
a. If more than one alarm, record all and proceed to step 2.
b. If this is the only alarm, check for continuity:
CAN Hi: 1MM-2 through SP
−
1 to ENCU
−
23.
CAN Lo: 1MM-4 through SP
−
4, to ENCU
−
24.
c. Replace ENCU.
2.
Check CAN Bus
a. Inspect connector pins & terminals on 1MM and1SVM. No damaged or corrosion in connections.
b. Check for CAN continuity:
CAN Hi: 1MM-2 through SP
−
1 to ENCU
−
23.
CAN Lo: 1MM-4 through SP
−
4, to ENCU
−
24.
If good continuity is not present, check connectors and wiring between terminals for damage, moisture
or corrosion.
3.
Check System
Clear active and inactive alarms. Start unit and monitor for additional “NO COMM” alarms.
Summary of Contents for Transicold X4 7300
Page 21: ...62 11637 1 6 1 3 SAFETY DECALS ...
Page 22: ...1 7 62 11637 62 03958 ...
Page 23: ...62 11637 1 8 ...
Page 24: ...1 9 62 11637 ...
Page 119: ...62 11637 SECTION 6 MESSAGECENTER PARAGRAPH NUMBER Page 6 1 MESSAGECENTER MESSAGES 6 1 ...
Page 278: ......