SECTION 06: ELECTRICAL
34
DOB 2490-2789 | X3-45 Commuter PA1605 Maintenance Manual (Final Version) – Sec 06 revised June 2017
Problem/symptom
Probable causes
Actions
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 cb5
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 switch 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 switch to the off position
and turn to the on position again. This
resets all "soft –fuses"
No backlighting in the
instrument cluster
Circuit breaker cb10 is
tripped or fuse f20 blown
Check / reset circuit breaker cb10
Check / replace fuse f20
