Battery Electrical Drain/Parasitic Load Test
BATTERY ELECTRICAL DRAIN/PARASITIC LOAD TESTTOOLS REQUIRED
SA9130Z Parasitic Load Tester
NOTE:
- Do not turn the parasitic draw test switch to the OFF position with the engine running. Damage will occur to the vehicle's electrical system.
- The test switch must be in the ON position when removing the fuses in order to maintain continuity in the electrical system. This avoids damaging the digital multimeter due to accidental overloading, such as a door being opened to change a fuse.
IMPORTANT: The ignition key must be removed from the ignition cylinder before parasitic load testing in order to deactivate the key-minder circuit.
1. Turn the ignition and all accessories OFF and remove key from the ignition switch.
2. Disconnect the battery negative cable from the battery negative terminal.
CAUTION: Refer to Battery Disconnect Caution in Service Precautions.
3. Install the male end of the SA9130Z to the battery negative terminal.
4. Connect the SA9130Z clamp to battery negative cable.
IMPORTANT: The alligator clamp on the parasitic load test device must be connected to the flat pad area on the battery negative cable. Do not connect the alligator clamp to the bolt on the battery negative battery cable.
5. Set the digital multimeter (DMM) to the MILLIVOLT scale.
6. Measure the current across the tester by putting the DMM probes into the 2 terminals of the parasitic load tester. The reading is obtained in volts. This reading is directly converted into milliamperes. The LED indicator on the test device will light if current draw is greater than 1 amp. This may indicate that a vehicle accessory is On.
7. Check and record the current reading.
8. Note the battery reserve capacity. Refer to Battery Usage.
1. Divide the reserve capacity by 4.
2. Compare this to the multimeter milliampere reading taken in the previous step.The parasitic current drain should not exceed this number.Example: If a battery has a reserve capacity of 100 minutes, the current drain should not exceed 25 mA.
9. Check the charging system if the vehicle has an acceptable amount of current drain. Refer to Charging System Test. Component Tests and General Diagnostics
10. When the vehicle has an unacceptable amount of parasitic current drain, remove each fuse one at a time until the current drain falls to an acceptable level. This will indicate which circuit is causing the drain. Refer to Power Distribution Schematics in Diagnostic Aids to diagnose exactly which part of the suspect circuit is causing the parasitic drain. In some cases a non-fused circuit or component, such as a generator, is the cause of excessive parasitic current drain.
NOTE: The test switch must be in the ON position when removing the fuses in order to maintain continuity in the electrical system. This avoids damaging the digital multimeter due to accidental overloading, such as a door being opened to change a fuse.
11. Repeat the parasitic current drain test procedure after any repair has been completed to make sure that the parasitic current drain is at an acceptable level.
12. When the cause of the excessive current draw has been located and repaired, remove the SA9130Z.
NOTE: Refer to Fastener Notice in Service Precautions.
13. Connect the negative battery cable.
Tighten the negative battery cable bolt to 15 N.m (11 lb ft).
14. Repeat parasitic current drain test procedure after any repair has been completed to make sure that the parasitic current drain is now at an acceptable level.
15. When the cause of the excessive current draw has been located and repaired, remove the parasitic load tester.