Thor Motor Coach 2009 Mandalay, Owner'S Manual

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MANDALAY
The automotive chassis alternator supplies power to both the automotive systems as well as
any coach battery. It also supplies power directly to the motorhome living quarters while the
vehicle’s motor is running. The condition of the motorhome’s electrical system and especially
the alternator, are of primary concern to you.
The alternator compensates for electrical usage in the motorhome - the power drawn by the
appliances, lights, fans and other 12 Volt powered items, as well as the charging of the
automotive and coach batteries.
If the alternator isn’t keeping pace with the draw on the motorhome’s electrical system while
traveling, it means you are working in a negative mode - more power is being used than the unit
is putting out.
This means that you are taking power out of the batteries. If you draw too much power from the
batteries, there may not be enough power left in the battery to start the motorhome or run any
of the appliances when you stop for a break or for the night.
So, always be aware of the alternator’s output. Also check the monitor panel frequently to see
that the coach batteries are at full charge. To insure an accurate reading, utilize a 12 Volt tester
on the batteries.
The alternator will charge at a higher rate right after the vehicle has been started. It replaces
the power that was used to start the vehicle. The charging should quickly go back to
“normal” and hold its own even when you turn on lights or appliances.
When stopped at a campsite that allows you the use of the shoreline, the 120 Volt electrical
system will recharge your coach battery.
When checking coach battery condition, turn on several interior lights to place a load on the
battery. Under heavy usage in warm weather, check the fluid level of the batteries often.
Low battery fluid level is very harmful to the battery’s longevity.
If the alternator shows a discharge while the motor is running, turn off appliances or lights to
see if a charge comes on or if the alternator indicates not charging. Then apply a drain on the
system to see if a discharge returns. If a discharge persists, contact your dealer.
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ELECTRICAL SYSTEMS
Chassis Alternator