I had this happen recently with a car. Battery was replaced, alternator checked, solenoid checked. Turned out to be a fuse that was causing a parasitic draw. Dealership didnt find it but local mechanic fix it shop did.
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Thank you for posting this!! My truck of 14 years has been having âbattery going deadâ issues the past several months. I thought I had read somewhere in research that a fuse issue could cause battery problems. I took the truck in to repair shop and asked them to look for issues specifically that would cause the battery to drain. They said nothing seemed to be wrong. The mechanic looked at me quizzically when I asked if it could be a bad fuse and dismissed the idea quickly. I left wondering if I imagined a fuse could be a problem. Will be looking into fuses now! Thanks again.
With parasitic draw, the issue is not with the fuse itself. The parasitic draw would be something like a glove compartment light that doesnât go out when the glove box door is closed. The mechanic checks the power draw at the fuses, since they are all typically in a central location, and it sure beats tracing out and checking each individual wire.
In the hypothetical case of a glove box light, the mechanic would find that electrical current is flowing through a fuse when there is supposed to be none. Then the procedure is to check out each item powered by that fuse. Those items will include the glove box light, which she will then discover is the culprit. So measuring current at each fuse narrows down the list of possible sources of parasitic draw to just a dozen or so, and eliminates the hundreds of other potential things powered through the other fuses in the fuse box.
And, there are many things on modern vehicles that use battery power all the time. One example is the vehicleâs computer. It has to remain on in order to receive the electronic signal from your key fob as you approach the truck to unlock the door. Thatâs one reason an electronics-filled new truckâs battery may lose enough power over a few weeks so that it wonât start.
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Thank you for the explanation. It makes more sense now. It does give me something to research and hopefully a parasitic draw will solve the mystery of the dying battery since they didnât find anything else wrong. On bright side, I am getting pretty good at connecting/disconnecting a battery - which is what I currently do, learning more about auto mechanics in general, and volt meters, etc. I have replaced the battery a couple times now when I didnât realize what was going on (thought someone didnât shut the door the first couple times; this truck requires a door slam to get the light to register to go off). I do try to drive it every week, but something is definitely drawing on the battery and it needs to be figured out! thanks again
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