Vehicles With Major Key Off Loads

WARNING: DO NOT ATTEMPT THIS TEST ON A LEAD-ACID BATTERY THAT HAS RECENTLY BEEN RECHARGED.

CAUTION: Do not crank the engine or operate accessories that draw more than 10A. You could blow the fuse in the meter.

NOTE: Vehicles equipped with Air Suspension or Load Leveling features will have temporary current drains that may last up to 70 minutes after ignition switch is turned OFF. These drains can range from 0.1 to 20 amps if the air suspension compressor is cycling. This action can often mask a concern and must be considered when evaluating test results. To test for this kind of drain proceed as follows.

1. Checks for current drains on the battery in excess of 50 mA with all the electrical accessories OFF and the vehicle at rest. Current drains can be tested with the following procedure:
a. Set ammeter to mA/A dc.
b. Disconnect battery terminal and momentarily touch cable to post.
3. Disconnect major key OFF load circuits.
4. Make sure interior lamp is OFF, if applicable. The current reading (current drain) should be less than 0.05 amp. If it is higher, disconnect fuses and starter relay leads to locate the problem circuit.

NOTE: If the drain is less than 0.05 amp, reconnect the major key-OFF load circuits, turn ignition switch to RUN and then OFF and wait 70 minutes to make sure they shut OFF properly. If current drain is still greater than 0.05 amp after 70 minutes, disconnect each of the components one at a time, until the cause of the current drain is located.