PREVOST X3-45 COMMUTER User Manual

SECTION 06: ELECTRICAL
68
DOB 1300-1556 | X3-45 Commuter PA-1648 Maintenance Manual Section 06 revised release October 2021
13. ALTERNATORS
Standard configuration includes three 24-volt
150A, self-regulated, belt driven, air-cooled HD
10 BOSCH alternators are used in the 24-volt
electrical system.
NOTE
For the complete removal/installation
instructions, refer to Maintenance Information
MI16-
17 Bosch HD10 alternator removal
and installation included at the end of this
section.
FIGURE 53: ALTERNATOR IDENTIFICATION
13.1 ALTERNATOR PERIODIC INSPECTION
When two alternators are
not charging, the charging
system warning light
illuminates. This telltale will
not illuminate if only one
alternator is defective.
However, a single
defective alternator can be
identified using the back-
probing method described
below.
charging system
warning light
13.1.1 Alternator identification
Cold side alternators are the one found on the
A/C compressor side. The hot side alternator is
the one located on the engine turbo side.
In this configuration, the multiplex system will
identify the alternator on the right (cold side) as
Upper Right, Lower Right and the left (hot side)
as Lower Left.
Cold Side (R.H.):
ALTERNATOR Up RH= upper right
ALTERNATOR Low RH=lower right
Hot Side (L.H.):
ALTERNATOR Low LH=lower left
13.1.2 Identifying a defective alternator using
the instrument cluster DID
1. On the DID (Driver Information Display),
select DIAGNOSTICS menu.
2. Select VIEW ACTIVE FAULTS and then
ELECTRICAL.
3. The active electrical system faults will
appear. Scroll through the active faults. You
will find one of the following messages:
MID (188) ELECTRICAL SYSTEM
PSID 34 ALTERNATOR Low RH
FMI (5) OPEN CIRCUIT
MID (188) ELECTRICAL SYSTEM
PSID 35 ALTERNATOR Up RH
FMI (5) OPEN CIRCUIT
13.1.3 Identifying a Defective Alternator –
Back-probing AE49 & AE52 Multiplex Modules
Method
Prerequisite conditions:
a) Engine running;
b) Parking brake applied.
Alternator Up RH =pin J1:20, module AE49
Alternator Low RH=pin J2:8, module AE52
Alternator Low LH= pin J2:9, module AE52
Back-probe pin 20 (AE49 J1:20):
• If multimeter reads 1-2 volts, the upper
R.H. alternator is defective;
• If multimeter reads 12 volts, you have
an open circuit;
• If multimeter reads 26 volts or greater,
the upper R.H. alternator operates
normally.
Back-probe pin 8 (AE52 J2:8) and a good
ground (use ground stud in the compartment):

PREVOST X3-45 COMMUTER Specifications

General

Engine	Volvo D13
Transmission	Allison B500
Fuel Type	Diesel
Length	45 ft (13.7 m)
Width	102 in (2.6 m)
Horsepower	500 hp
GVWR	54, 000 lbs
Height	141 in