PREVOST H3-45 2023 Operator's Manual page 249

Problem / Symptom
None of the Multiplexed
functions are operating,
including the basic limp-
home functions (door
opening, flashers, wipers
in speed 1)
"FLIP REAR BREAKER
TO INITIATE I/O
MODULES
PROGRAMMING" pop-
up message appears in
the DID
Note: The sunshades are
still functioning since
these are not multiplexed
Many of the non-
essential secondary
functions are not
functioning (interior
lighting, driver's area
lighting, wiper speed 2
and intermittent).
Marker lights and
clearance lights are
turned ON when setting
ignition to the ON
position.
No temperature control in
the passenger area
Passenger temperature
display indicates two
dashes "--"
Probable Causes
The program version in the
MCM is different than the
program in the I/O modules
and the MCM is forcing all
I/O modules to stay inactive
The MCM module does not
receive 24 V power.
The DL0 (BBUS MUX)
network is not working. It
could be caused by a short
on the network, an open
circuit, a problem with the
MCM or the MCM being
disconnected from
network.
Problem with
temperature sensor located
in the evaporator
compartment air intake or
the sensor wiring
PA-1652 Operator's Manual H3-45 Coach
Multiplex Troubleshooting B-3
1. Engage the auto- programming of the I/O
modules: Turn the ignition key to the ON
position, trip and reset circuit breaker CB6.
2. The DID
AUTOPROGRAMMING
PLEASE WAIT" until the reprogramming is
complete.
1. Check / reset circuit breaker CB6. Check /
replace fuse F1
2. Operate in limp- home mode by starting the
vehicle from the engine compartment (REAR
START). All functions essential to drive are
available
the
To close and lock the door, pull the door
manually up to its closed position and it will
lock by itself. The door opening button is
still functioning
the Instruct the driver to manually control the
temperature by playing with the passenger
set point. Set above 22°C (72°F) to heat
and below 22° C (72°F) to cool
Actions
indicates "MUX
I/O MODULE