PREVOST X3-45 COACH 2018 Operator's Manual page 210

Appendix B – Troubleshooting Guide for Multiplex Vehicles
4
Problem/Symptom
Rear flashers not
functioning
Stoplights and center
stoplights not functioning
Engine is overheating and
radiator fans do
engage
The A/C compressor
clutch does not engage
Evaporator fan not
functioning
Probable Causes
Module AE51 is not powered
or is faulty
Module AE52 or AE49 is not
not powered or is faulty
Module AE54 is not powered
or is faulty
Circuit breaker CB3 tripped
Module AE54 is not powered
PA1627 X3-45 Operator's Manual
Actions
3. Check / replace fuse F21
4. Probe gray connector on module to
see if it is powered.
1. Check the SYSTEM DIAGNOSTIC
menu of Driver Information Display
(DID). Select FAULT DIAGNOSTIC
and ELECTRICAL SYSTEM. The
message "No Response ModA51,
Active" indicates a power problem on
the module. (A CAN network problem
would show the same message but
doesn't produce this symptom).
2. Check / reset circuit breaker CB8
3. Check / replace fuse F107
4. Probe gray connector on module to
see if it is powered.
1. Check the SYSTEM DIAGNOSTIC
menu of Driver Information Display
(DID). Select FAULT DIAGNOSTIC
and ELECTRICAL SYSTEM. The
message "No Response ModA52/
ModA49, Active" indicates a power
problem on the module. (A CAN
network problem would show the
same message but doesn't produce
this symptom).
2. Check circuit breaker CB5
3. Check / replace fuse F133, F134
4. CB201-CB208
1. Check the SYSTEM DIAGNOSTIC
menu of Driver Information Display
(DID). Select FAULT DIAGNOSTIC
and ELECTRICAL SYSTEM. The
message "No Response ModA54,
Active" indicates a power problem on
the module. (A CAN network problem
would show the same message but
doesn't produce this symptom).
2. Check / reset circuit breaker CB5
3. Check / replace fuse F135
4. Probe gray connector on module to
see if it is powered.
1. Check circuit breaker CB3
2. Check relay R12