Thor Motor Coach CLASS B Owner'S Manual Download

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E L E C T R I C A L S Y S T E M

T H O R M O T O R C O A C H | M A D E T O F I T

Chassis Alternator

The 12 volts DC chassis alternator supplies power to both the

automotive systems as well as the auxiliary batteries while the

motorhome’s engine is running. The alternator compensates

for electrical usage in the vehicle, the power drawn by lights,

fans, and other 12 volt powered items, as well as charging of

the automotive and auxiliary batteries.

When driving, if the alternator is not keeping pace with the

draw on your motorhome’s electrical system, it means it is

working in a negative mode; more power is being used than

the alternator is capable of supplying. If you draw too much

power from your batteries there may not be enough power

left to start the motorhome or run the 12 volts DC appliances

when you stop for a break or for the night.

The alternator will charge at a higher rate right after the

motorhome has been started, replacing the power used to

start the vehicle, but the charging should quickly drop back

to ‘normal’ and hold its own even when you turn on lights or

appliances.

If the alternator shows a discharge while the vehicle’s engine

is running, turn OFF appliances and lights to see if a charge

comes on or if the alternator indicates ‘neutral.’ Then apply a

load (turn ON a 12 volt DC appliance) on the system to see if a

discharge returns. If a discharge persists, your alternator may

not be working correctly; contact your dealer.

NOTE: If your motorhome is equipped with the op-
tional Re(li)able Battery Power System, there is an
additional alternator installed on your vehicle that is
specifically designed to charge the lithium-ion battery
system.

Battery Charging

It is important to keep the auxiliary battery(ies) in a condi-

tion of full or near-full charge. Doing so will ensure you will

have enough stored 12 volt DC energy when needed. Battery

charging is accomplished by:

• Automatic charging through the converter (shore power

or generator);

• With the vehicle engine running, auxiliary battery(ies)

are charged via the chassis alternator (when Master

Battery Disconnect Switch is ON);

• Auxiliary battery charging via solar charging system

(equipped as standard, optional, or customer installed).

Take time to turn off all lights or other 12 volt accessories

when not in use. Connect the motorhome to a 120 volt AC

external source or run the generator whenever possible. Doing

so will keep the auxiliary batteries charged.

The auxiliary batteries are a deep-cycle type and are capable

of being deeply discharged and rebound to full capacity when

recharged. Due to their large energy storage capacity, the auxil-

iary battery(ies) may take up to 24 hours to completely recharge.

If for any reason, you recharge a auxiliary battery with a

charger or power source other than what was supplied as part

of the motorhome’s original electrical system, make sure to

follow all battery maintenance and safety instructions from

the battery and battery charger manufacturers.

NOTE: The Master Battery Disconnect Switch must
be ON in order to charge the battery(ies) by any on-
board method described in the following sections.

Battery Access

The auxiliary batteries are located underneath the vehicle,

secured by mounting brackets. The vehicle must be raised to

access the batteries. Always secure a raised vehicle with jack

stands or other devices. Refer to the vehicle manufacturer’s

owner’s manual for proper jacking procedures.

For long battery life, it is important to keep your motorhome

batteries fully charged as much as possible. Turn OFF lights

and other 12 volts DC components when they are not being

used. Connect the motorhome to a 120/220 volts AC power

source (shore power) whenever possible.

Due to the mounting position of the auxiliary batteries,
they may be subject to damage due to road hazards or
other travel-related issues.