Originally Posted by
onehundred80
It is under Battery System in the Service Manual.
STANDARD PROCEDURE - IGNITION-OFF DRAW TEST
The term Ignition-Off Draw (IOD) identifies a normal condition where power is being drained from the battery with
the ignition switch in the Off position. A normal vehicle electrical system will draw from five to thirty-five milliamperes
(0.005 to 0.035 ampere) with the ignition switch in the Off position, and all non-ignition controlled circuits in proper
working order. Up to thirty-five milliamperes are needed to enable the memory functions for the Powertrain Control
Module (PCM), and other modules which may vary with the vehicle equipment.
A vehicle that has not been operated for approximately twenty days, may discharge the battery to an inadequate
level. When a vehicle will not be used for twenty days or more (stored), remove the negative battery cable from the
battery. This will reduce battery discharging.
Excessive IOD can be caused by:
² Electrical items left on.
² Faulty or improperly adjusted switches.
² Faulty or shorted electronic modules and components.
² An internally shorted generator.
² Intermittent shorts in the wiring.
If the IOD is over thirty-five milliamperes, the problem must be found and corrected before replacing a battery. In
most cases, the battery can be charged and returned to service after the excessive IOD condition has been corrected.
1. Verify that all electrical accessories are off. Turn off all lamps, remove the ignition key, and close all doors. If the
vehicle is equipped with an illuminated entry system or an electronically tuned radio, allow the electronic timer
function of these systems to automatically shut off (time out). This may take up to three minutes. See the Electronic
Module Ignition-Off Draw Table for more information.