Navistar ProStar+, Operation And Maintenance Manual

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Operation
Circuit Breakers, Fuses and Fusible Links
WARNING
To prevent property damage, personal injury, and
/ or death, do not increase size of fuse or circuit
breaker or change type of breaker supplied
with your truck, as this could cause wiring to
overheat and possibly burn. Electrical circuits
are designed with a particular wire gauge to meet
the fuse and circuit breaker current rating.
• Electrical circuits are protected by the electrical system
controller, circuit breakers, fuses, or fusible links. For the
size and location of circuit breakers, fuses and fusible
links, please refer to the
Maintenance Intervals and
Specifications section of this manual.
• Fusible links consist of a length of lighter gauge wire in
a circuit. In case of a short or overload, the fusible link
opens (burns out) to protect the remainder of the circuit.
Repair consists of installing a new fusible link with the
same gauge wire as the opened fusible link.
• Circuit breakers interrupt the circuit when an overload
or short occurs. Manual circuit breakers (Type III) can
be reset by depressing the reset button on the breaker.
Headlamp and wiper circuits are protected by the Body
Controller. Type II circuit breakers will reset automatically
if the short is removed from the circuit.
• The various electrical units in the cab and engine
compartments are protected by either fuses or circuit
breakers. The power distribution center is located within
the instrument panel (glove box area) on the passenger
side of the vehicle.
Electrical Load Control and Shedding (ELCS)
Electrical Load Control and Shedding (ELCS) is an optional
feature (standard with sleepers) intended to provide a
convenient means of automatically shutting down electrical
loads overnight in order to conserve energy and deliver sufficient
power to start the engine. The system is active when the engine
is not running, regardless of key state. The ELCS system does
not include provisions for shutting down 120-VAC circuits.
The ELCS will begin a sequence of events when the measured
battery voltage is at or below 12.1 VDC for a period of 30
seconds. The sequence of events will first start with providing
the visual alert LOAD SHEDDING to the vehicle operator for
at least 30 seconds.
An audible alert, which consists of a
continuous tone greater than 3 seconds and less than 6 seconds
in duration, will coincide with the start of the visual alert.
The audible alert can be disabled by a vehicle maintainer if
desired. The sequence will then disable a predefined group
of features / electrical loads. These will remain disabled until
the vehicle's key switch transitions to the Accessory or ON
positions, and the measured voltage is above 12.1 VDC.
Engine
The engine for this vehicle is an electronically controlled diesel
engine. A separate Engine Control Module (ECM) monitors and
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