you need a voltage drop test to find the drain first
Voltage drop test ,for battery drain checking
1- need a Voltmeter
2- settings on voltmeter will be on milli amps.
3- go across all the fuses in the car and see which one is reading higher than 0.3 0.5 milli amps
than that will be the circuit we need to address for drainage .
also make sure the charging system is giving 14 volts ,with all loads on a/c ,headlight, flasher
Let me know if you need anything else on it ,just reply back & we can continue troubleshooting
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