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Old 05-22-2018, 07:08 PM   #1
a400tool
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Default Battery Discharge Light.

Keep getting a battery discharge light.



So far I have replaced the battery, the alternator, the alternator plug. The positive and negative battery cables.



I have checked all grounds throughout the chassis, and the light still remains.


The car starts and runs normally. No lights for a few seconds, and then as soon as you rev the engine, the discharge light and the ABS light come on...


Electrics not my strong point.



Any ideas....
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Old 05-22-2018, 10:55 PM   #2
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Try unplugging the brake light failure module as a test. Its located behind the center plastic panel near the trunk lock on the inside. If that solves the problem, you might have a water leak or water has leaked onto the module. I fixed mine by opening it up and cleaning the corrosion off the circuit board that was shorting it. I put it into a plastic bag that helped prevent water from getting into it again and bolted it back on. It gave me similar weird wonky warning lights that didn't make sense. I guess the failure module needs a failure module. Another weird thing happened when the AC/heat blower motor brushes wore down to a nub and shorted. As a next step, try unplugging the blower motor under the passenger side kick panel. Unplug the black air temp thermostat coils. It's very close to it as well. It's got 3 coils of wire. The delicate thin gauge one always burns out and you loose low fan motor speed. I replaced mine by coiling a similar small gauge paperclip around a pencil and substituting it for the broken coil. Soldering skills and materials are required.

Good luck, Bru

Last edited by Bru; 05-22-2018 at 11:30 PM.
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Old 05-22-2018, 10:57 PM   #3
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Thanks. I'll try that.
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Old 06-13-2018, 10:23 AM   #4
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Not related to the your battery discharge issue, but Bru's note about the coils may have just solved my issue with the low speed setting on the fan!
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Old 09-14-2018, 07:31 AM   #5
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Don't forget to check the fuses also.
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Old 11-15-2018, 12:58 AM   #6
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Found the ground from the coil packs to the head to be the culprit!
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