IOD (Ignition Off-Draw) What, Where, Why
If you will not be using your vehicle for more than 21 days, you may want to take steps to preserve your battery. You may:
• Disengage the mini-fuse in the Power Distribution Center labeled IOD (Ignition Off-Draw).
• Or, disconnect the negative cable from the battery.
From the service manual:
OPERATION
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 Totally Integrated Power Module (TIPM) fuse cavity 18 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.
The IOD fuse can be used by the vehicle owner as a convenient means of reducing battery depletion when a vehicle
is to be stored for periods not to exceed about thirty days. However, it must be remembered that disconnecting
the IOD fuse will not eliminate IOD, but only reduce this normal condition. If a vehicle will be stored for more than
about thirty days, the battery negative cable should be disconnected to eliminate normal IOD; and, the battery
should be tested and recharged at regular intervals during the vehicle storage period to prevent the battery from
becoming discharged or damaged.
REMOVAL
NOTE: When removing or installing the IOD fuse, it is important that the ignition switch be in the Off position.
Failure to place the ignition switch in the Off position can cause the radio display to become scrambled
when the IOD fuse is installed. Removing and installing the IOD fuse again with the ignition switch in
the Off position will usually correct the scrambled radio display condition.
1. Turn the ignition switch to the Off position.
2. Remove the cover from the Totally Integrated Power Module (TIPM).
3. Remove fuse 7/8 from the TIPM.
INSTALLATION
1. Insert fuse 7/8 into the Totally Integrated Power Module (TIPM).