RAM 3500 Truck 4WD L6-5.9L DSL Turbo VIN C (2002)
Power Interrupt Connector/Switch: Description and Operation
Fig. 3 Ignition-Off Draw Fuse
IOD FUSE
All vehicles are equipped with an Ignition-Off Draw (IOD) fuse (Fig. 3) that is disconnected within the Junction Block when the vehicle is shipped from
the factory Dealer personnel are to reconnect the IOD fuse in the junction block as part of the preparation procedures performed just prior to new vehicle
delivery.
The left end of the instrument panel cover has a snap-fit fuse access panel that can be removed to provide service access to the fuses in the junction block
. A finger recess is molded into the access panel for easy removal. An adhesive-backed fuse layout map is secured to the instrument panel side of the
access panel to ensure proper fuse identification. The IOD fuse is a 10 ampere mini blade-type fuse. The fuse is secured within a black molded plastic
fuse holder and puller unit that serves both as a tool for disconnecting and reconnecting the fuse in its junction block cavity, and as a fuse holder that
conveniently stores the fuse in the same junction block cavity after it has been disconnected.
Circuits Included With IOD Fuse
*
Cargo Lamp
*
CHMSL
*
Diagnostic Connector
*
Dome Lamp
*
Glove Box Lamp
*
Map/Reading Lamps
*
Power Mirrors
*
Radio
*
Under Hood Lamp
The term ignition-off draw identifies a normal condition where power is being drained from the battery with the ignition switch in the OFF position. The
IOD fuse feeds the memory and sleep mode functions for some of the electronic modules in the vehicle as well as various other accessories that require
battery current when the ignition switch is in the OFF position, including the clock. The only reason the IOD fuse is disconnected is to reduce the normal
IOD of the vehicle electrical system during new vehicle transportation and pre-delivery storage to reduce battery depletion, while still allowing vehicle
operation so that the vehicle can be loaded, unloaded and moved as needed by both vehicle transportation company and dealer personnel.
The IOD fuse is disconnected from JB fuse cavity 12 when the vehicle is shipped from the assembly plant. Dealer personnel must reconnect the IOD fuse
when the vehicle is being prepared for delivery in order to restore full electrical system operation. Once the vehicle is prepared for delivery, the IOD
function of this fuse becomes transparent and the fuse that has been assigned the IOD designation becomes only another Fused B(+) circuit fuse. The
IOD fuse serves no useful purpose to the dealer technician in the service or diagnosis of any vehicle system or condition, other than the same purpose as
that of any other standard circuit protection device.
