Electrical Accessory Connection Points - Mack Granite GU Series Operator's Handbook Manual

MAINTENANCE AND LUBRICATION 299

Electrical Accessory Connection Points

CAUTION
The electrical systems on all MACK chassis include a circuit breaker located in the
ground circuit. Any additional electrical components that may be added MUST not
be connected directly to the battery or negative connection of the starter. Doing
so may defeat the protection provided by this circuit breaker. Components may be
ground connected to other locations, such as frame or engine grounding points.
This MACK chassis is ready for convenient installation of electrical
accessories. Use only the designated CB jacks on the dashboard, or battery
post (12 volts), ignition, ground post, buffered tachometer (RPM) output, and
buffered speedometer (MPH) output connections available on the electrical
equipment panel. Each connection point is described below.
Battery Post (BATT)
This is a 12-volt, unswitched battery power connection. It can be used to
power external devices that require power at all times, even when the key is
turned off. This source is protected by a 20-amp circuit breaker.
Ignition Post (IGN)
This is a 12-volt, switched battery power connection. It can be used to power
external devices that require power only when the key is turned on. This
source is protected by a 15-amp circuit breaker.
Ground Post (GND)
This is a ground connection. It can be used as a power return connection
for external devices.
WARNING
The tachometer output, speedometer output, and serial links A and B are
for specific hookups. These terminals should be used only for their specified
purposes and connection to these terminals should be done only by a qualified
service technician.