SECTION 06: ELECTRICAL
DOB 2490-2789 | X3-45 Commuter PA1605 Maintenance Manual (Final Version) – Sec 06 revised June 2017
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connector first, then the grey one and finish
with the black connector. To disconnect the
black connector, slide downwards the red
latch. Remove the lower screw that holds the
cable attachment rod onto the floor portion of
the panel and flip the rod up, this will relieve
the IO-B module, see Figure 28).
3. Reset circuit breaker cb6. Doing so will
initiate the I/O reprogramming.
Note
Jb6 is a wake-up pin. Ja15 output remains
active for 5 minutes after jb6 is inactive.
When initiating reprogramming:
Switch sw83 (ignition key) remains closed,
providing 24-volt on jb6, i/o modules and r18.
All modules get power.
Cb6 is tripped and reset which is forcing mcm
reboot.
When resetting cb6, all modules get power,
mcm goes into “start mode”. I/o modules
needing new program will request
reprogramming to mcm while in “start mode”.
4. The DID indicates "mux autoprogramming i/o
module please wait" until the reprogramming
is complete unless a higher priority message
must be displayed. If this is the case, press
escape button repeatedly to acknowledge the
higher priority messages.
5. Check the
diagnostics
menu of the driver
information display (DID). Select
fault
diagnostics
and
electrical system
. Verify
the fault message to be certain the module is
reprogrammed. If the module is not
reprogrammed, the message “axx not
responding” appears where axx is the
module number (ex: a41, a42…etc).
4.14.2 Replacing The MCM
1. Set the ignition key to the on position and
leave in that position at all time while
performing this procedure.
2. On rear electrical junction panel, trip circuit
breaker cb6.
3. Replace the module.
4. Reset circuit breaker cb6.
5. The vehicle specific multiplex program needs
to be uploaded in the mcm.
4.14.3 Uploading the vehicle specific multiplex
program in the mcm
A laptop computer running windows xp or
windows 7 must be connected to the rs232
serial port db9 connector (identified c226) found
on the front service compartment electrical
panel. Please contact your Prevost service
representative in order to get the vehicle specific
multiplex program. Save the specific multiplex
program on your computer desktop.
FIGURE 29: DB9 CONNECTOR AND MCM LOCATION
Set the ignition switch to the on position and
leave in that position at all time while performing
this procedure.
1. Assure that the vehicle battery charger is
connected to 120-volt and that the laptop
computer battery is fully charged.
2. Connect the laptop computer to the mcm
through the db9 connector. To do so, you
need (see Figure 30):
1x usb to serial db9 rs232 adapter (sold at
staples);
1x prevost interface cable p/n 066009;
