PREVOST X3-45 VIP 2015, Owner'S Manual

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Appendix B – Troubleshooting Guide for Multiplex Vehicles 4
Problem/Symptom Probable Causes Actions
3. Check / replace fuse F65.
4. Probe gray connector on module to
see if it is powered.
Evaporator fan not
functioning
Circuit breaker CB4 tripped
Module A54 is not powered
or is faulty
1. Check / reset circuit breaker CB4.
2. Check the Diagnostics menu of Driver
Information Display (DID). Select Fault
Diagnostics 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).
3. Check / reset circuit breaker CB7.
4. Check / replace fuse F67, F68.
5. Probe gray connector on module to
see if it is powered.
HVAC condenser fans not
functioning in speed 1 Module A54 is not powered
or is faulty 1. Check the Diagnostics menu of Driver
Information Display (DID). Select Fault
Diagnostics 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 CB7.
3. Check / replace fuse F67, F68.
4. Probe gray connector on module to
see if it is powered.
Fire alarm telltale light and
audible alarm always ON
and there is no fire or high
temperature in the engine
compartment Short-circuited fire sensor or
defective sensor Prior to start the vehicle, cycle the ignition
key to the ON position, OFF position and
then ON position again and then start the
vehicle. This will deactivate the fire alarm
function. This has to be repeated each
time the vehicle is re-started.
The vehicle is parked and
the electrical horn is acti-
vated to indicate a fire in
the engine compartment
but there is no fire Short-circuited fire sensor or
defective sensor Cycle the ignition key between the ON and
OFF position twice within 3 seconds. This
will deactivate the fire alarm function. This
has to be repeated each time the vehicle
is parked.
A single light, a group of
LED lights or another
function of the vehicle is
not functioning The multiplex outputs are
protected in current by an
internal “soft-fuse”. When an
output is shorted, it turns
OFF and stays OFF until the
"soft-fuse" is reset Turn the ignition key to the OFF position
and turn to the ON position again. This
resets all "soft –fuses".