Battery Drain Test - General Procedures

Check

Click here to view the parasitic draw test.

1. 1
   If equipped, deactivate the approach detection feature.
2. 2
   Make sure the fuse box can be accessed without turning on the interior lamps or the underhood lamp.
3. 3
   Drive the vehicle for at least 5 minutes at a speed greater than 48 km/h to activate the vehicle systems.
4. 4
   Leave the vehicle with the ignition off for at least 40 minutes to allow the modules to time out.
5. 5
   Connect a fused jumper wire (30 A) between the battery negative cable and the battery negative terminal to prevent the modules from resetting.
6. 6
   Disconnect the battery negative cable from the battery negative terminal without breaking the fused jumper wire connection.
7. 7
   Connect a multimeter between the battery negative cable terminal and the battery negative post.
8. 8
   Remove the fused jumper wire.
9. 9
   Note the current draw. Current draw varies from vehicle to vehicle depending on equipment level. Compare with a similar vehicle for reference.
10. 10
    If the current draw is excessive, remove the fuses from the Totally Integrated Power Module (TIPM) one at a time and observe the drop in current.
11. 11
    When the current draw drops to an acceptable level after removing a fuse, the circuit containing the excessive draw has been found. Reinstall the fuse and allow the vehicle to stand with the key removed from the ignition for at least 40 minutes so the modules time out and power down again.
12. 12
    The excessive draw can be isolated by continuing to remove subsystem fuses and disconnecting components. Do not reinstall fuses or reconnect components until testing is complete. To properly isolate each circuit, it may be necessary to remove all fuses, then install one fuse and observe the current draw, remove that fuse and install the next fuse. Continue this process with each fuse.
13. 13
    If the excessive current draw is related to a specific module, check whether the module inputs are the cause. Refer to the appropriate system operation and component description section to identify the inputs (wired or network messages) received by the module.
14. 14
    Refer to the wiring diagrams manual for circuits that operate directly from the battery without passing through the TIPM or other fuse box(es). If the current draw is still excessive, disconnect these circuits until the draw is found. Disconnect the generator(s) from the electrical connections and repeat the check if the draw cannot be found. The generator(s) may have an internal short circuit causing a current leak.
15. 15
    If equipped with one-touch window-up function, perform the window motor initialization after disconnecting the negative battery cable from the battery.
    Refer to: Power Door Window Motor Initialization (501-11 Glass, Frames and Mechanisms, General Procedures).