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A friend has a 2008 that keeps discharging the battery. The battery is less than one year old and has been checked to be good in all aspects. The OnStar fuse has been pulled but still a battery drain exists. The next step is to check for a parasitic drain with a multi-meter. What is the acceptable drain on the battery with the car asleep and all systems turned off?
Unless it is a specific value in Service Info which it is not on my 2008 the drain is the reserve capacity of the battery in minutes divided by 4…100 minute RC would be 25 milliamps acceptable drain…video below…you DON’T pull fuses (may wake up a module) but instead do a voltage drop on each fuse with a DVOM…2008 Service Info below.
Battery drain question
