Mandalay 2006 Presidio, Manual

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It is a good idea to keep additional fuses on hand in the motorhome. Replacement fuses are
available at most service stations, hardware and automotive supply stores. Remember that
the replacement fuse must be the same amperage rating as the original.
AUTOMOTIVE 12 VOLT SYSTEM
The primary point to keep in mind about the unit’s 12 volt system is that the automotive
chassis alternator supplies power to both the automotive systems as well as any coach
battery and directly to the motorhome living quarters while the vehicle’s motor is running.
Thus, of primary concern to you is the condition of the motorhomes electrical system and
especially the alternator.
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 motorhomes electrical system, while
driving down the road, 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, replacing
the power that was used to start the vehicle, but 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.
7-9
ELECTRICAL SYSTEMS
2005 PRESIDIO