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Check For An Excessive Current Draw





CHECK FOR AN EXCESSIVE CURRENT DRAW

1. Turn the ignition off.
2. Disconnect the Negative Battery cable (ground).
3. Using a multimeter, set the multimeter leads up to properly measure Amperage.
4. Connect the ground lead that is plugged into the COM port of the multimeter to the Negative Battery cable.
5. Connect the other lead of the multimeter that is plugged into the Amp port of the multimeter to the negative battery post/terminal.

CAUTION: Do not crank the engine or turn on any accessories that may draw more than 10 Amps. You may open the protective fuse in the multimeter.

NOTE: To get a more accurate reading and current draw, wait 20 minutes to make sure all modules have powered down before continuing. Some modules may stay powered up longer than others.

6. While monitoring the amperage reading, remove a fuse and see if the amperage drops.
7. If the amperage does not drop, install that fuse you just removed and remove the next fuse.

Does the amperage drop to between 0.02 to 0.04 of an Amp when removing any fuses.

Yes

- Use the wiring application as a guide to find out what components or modules are powered by the fuse. At this point you can install the fuse and begin disconnecting the components powered by the fuse. When the amperage drops after disconnecting a component you will know which component is at fault. It is important to know how long some modules are supposed to remain awake. You don't want to replace a component that is operating normally.

No

- The condition that originally caused the draw may not be present at this time.
- Look for any chafed, pierced, pinched, or partially broken wires.
- Look for broken, bent, pushed out or corroded ground terminals.
- Perform any Technical Service Bulletins that may apply.