Question about automobile battery charger

Bad amp switch on DieHard battery charger. Does anyone know if I can bypass the two 10 and 50 amp switch to jest say up 50 amp. I know I wouldn’t want to leave that on a battery for a long, butt in case of emergency could I take the old switch out and directly wire it to work on a either the 2amp, 10 am or 50 amp setting. Does anyone know what wires to connect on the back of the switch for each setting?

I would look for a replacement switch, if it is only the switch, or just buy a new battery maintainer. Post your model, I can see what I can find.

For the last 30-40 years, all I have used it the $30-40 chargers. They’ve worked just fine for home use and I’m only on my second one. I’d just consider buying a replacement and be done with it.


If I ever have to replace my 50+ year old 6 amp Sears battery charger I would buy thr 2-10-50 one that HF has on sale for $29 repeatedly.

Wouldn’t it be a lot safer and easier to just buy a new battery charger charger?

Reminds me of the time I had a new generator. For years I had to fiddle with the carberator and use starting fluid to start it. After years of frustration, I finally searched for a carberator replacement and low and behold, they were only $15. Installed it and it started and ran perfectly. A month later, the generator half wore out and I had to buy a whole new generator. Sometimes it’s best not to assume repairing is not always better than replacing.

Yep. I’ve still got one I bought at Menards back in the late 90’s. It’s ugly and beat up, but still works. You can get nice ones wtih automatic trickle charging for less than 50 bucks nowadays. Why mess with re-wiring the old one. Especially since

means you shouldn’t be messing with it in the first place.

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I think I must have the same charger as you do.

Meter on the left side?

I bought mine in 1980. That was when Sears had quality items. I still have several Craftsman black garden hoses. And my Fisherman’s Knit socks lasted me two decades! :slight_smile:

Its possible to that, at least in theory. But even a [professional electrical engineer would be leary of doing that job unless they had an electrical schematic of the battery charger to refer. 12 volts at 50 amps is quite a bit of wattage. There’s safety circuity in the charger’s circuits to minimize the chance of overheating, overcharging, fires, etc, and you’d want to know for certain you weren’t inadvertently bypassing those safety functions by monkeying with the switch.

I’d just replace the switch, assuming you have a model 200.71222 Diehard battery charger

I’m going by the 2-10-50 amps

Yep, gauge on left, gray body. I have had to reolace the fuse twice.