Operation CHARM: Car repair manuals for everyone.

Parasitic Draw Test

Parasitic Draw Test:





Tools Required:
J 38758 Parasitic Draw Test Switch Ammeter with a least 10 amp measurement capabilities.

NOTE: The parasitic draw test switch should never be turned to the OFF position with the engine running; damage could occur to the attached ammeter or the vehicle electrical system.

1. Remove battery cable from battery negative terminal.
2. Install the parasitic draw test switch male end to negative battery terminal.
Tighten: J 38758 to 15 N.m (11 lb. ft.).
3. Turn test switch knob to the OFF position.
4. Install negative battery cable to female end of the test switch tool.
Tighten: Negative battery cable bolt to 15 N.m (11 lb. ft.).
5. Turn the test switch knob to the ON position.
6. Road test vehicle while activating all accessories (radio, A/C etc.).
7. Turn ignition switch to the Lock position and remove ignition key.
8. Set ammeter to the 10 amp scale and connect to terminals on test switch tool.
9. Turn test switch tool knob to the OFF position to allow current to flow through the ammeter.
10. Check current reading. When current reading is at or below two amps, turn the test tool knob to the "ON" position (to maintain continuity in the electrical system) and switch down to the two amp scale for a more accurate reading when drain test tool knob is turned "OFF."

IMPORTANT: Always turn the test switch tool knob to the "ON" position before removing each fuse to maintain continuity in the electrical system and to avoid damaging the ammeter due to accidental overloading (i.e. opening door to change fuse. etc.).

11. When current draw is less than 30 milliamps, check charging system for proper operation. When current draw is above 30 milliamps, remove system fuses one fuse at a time until the current draw returns to a value less than or equal to 30 milliamps. Perform steps 8 through 10 each time a fuse is removed.

IMPORTANT: Repeat parasitic current drain procedure after any repair has been completed.

12. When cause of excessive current draw has been located and repaired, remove current drain test tool and connect negative battery cable to negative battery terminal.
Tighten: Negative battery cable bolt to 15 N.m (11 lb. ft.).