Electrical System
367
Figure 9-12, Charging System Schematic
8. Connect voltmeter to regulator POS terminal. This is the input voltage to the regulator.
a. If voltmeter reads 24–28 volts and voltage in Step 7 was less than 28 volts and the ground
connection (Step 6) is good, the regulator is defective.
b. If the voltmeter reads 0 or less than 24–28 volts, proceed to the next step.
9. Move to the ignition relay and connect the voltmeter to terminal 87.
a. If voltmeter reads 24–28 volts, there is a problem in the wiring between the alternator POS
terminal and the ignition relay.
b, If voltmeter reads 0 volts, proceed to next step.
10. Connect voltmeter to ignition relay terminal 30. This is the 24 volt input.
a. If voltmeter reads 24–28 volts, ignition relay is not energized. This relay is energized by I/O
controls. Refer to ladder charts in
Multiplex Schematics
.
b. If voltmeter reads 0 volts, check fuse, then troubleshoot 24 volt input circuit wiring.
ALTERNATOR
FUSE
325A
FUSE
9A
FUSE
9A
REGULATOR
BREAK-OUT TOOL
(Do Not Pierce
Wire Insulation)
F1
F2
POS RELAY
GND
GRN
RED
FLD
GND
GND
IGN BATT SENSE
24V
BATTERY
24V
BATTERY
+
TO
NO-CHARGE
RELAY
FROM
I/O CONTROLS
IGNITION RELAY
87
30
6
2
1
5
4
3
Summary of Contents for LOW FLOOR
Page 18: ...Specifications 18...
Page 58: ...Preventive Maintenance 58...
Page 110: ...Engine 110...
Page 138: ...Transmission Driveline Rear Axle 138...
Page 182: ...Suspension 182...
Page 260: ...Air System 260...
Page 420: ...Electrical System 420 Deutsch DT Series Connectors...
Page 421: ...Electrical System 421...
Page 422: ...Electrical System 422 Deutsch HD 10 Series Connectors...
Page 423: ...Electrical System 423...
Page 424: ...Electrical System 424 Deutsch HD 30 Series Connectors...
Page 425: ...Electrical System 425...
Page 442: ...Heating Air Conditioning 442...
Page 492: ...Body and Interior 492 Figure 11 33 USSC Seat Assembly...
Page 493: ...Body and Interior 493 Figure 11 34 USSC Seat Suspension Assembly...
Page 495: ...Body and Interior 495 Figure 11 37 Seat Air Connections...