Screw Type Battery Cut off Switch - Safe For Modern Cars?

Old 08-30-08, 11:40 PM
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Screw Type Battery Cut off Switch - Safe For Modern Cars?

Since my garage queen is used infrequently, I'd like to install this cut off switch on my new battery to reduce the chances of being discharged. Is it safe, particularly on the electronics? I have a 2004 F150. If it is safe, should be connected to the negative or positive side?

Thanks in advance.
Old 08-31-08, 05:38 AM
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very probably the negative side.
at least weekly you should hook up the battery
to a slow-charger though, with the
device still disconnected (turnable knob upwards).
it also cancels out the radio and clock etc programming.
80 percent chance that applies to you car which is
18 or so years newer than mine
Old 08-31-08, 06:48 AM
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Besides the clock, radio, etc, you may lose your ECM programming. This will cause the engine to have to relearn its settings, and may cause initial rough/innefficient running when you do drive it. Esp if it's just a short trip. Takes several diff driving cycles for the computer to complete the re-learn.

I think I'd leave it connected and put the trickle charger on it. They have smart chargers now that won't overcharge the battery.

I'm sure one of the Pro's may have more.
Old 08-31-08, 08:34 AM
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I cant see no problem with it.
As long as the major loads are off of it while connecting and disconnecting.
I would install it on the positive side
Old 08-31-08, 01:40 PM
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you would be better off to install a battery maintainer to keep the battery charge up. I recently read of a very good one in my goldwing road riders magazine. manufactured by PulseTech Products, called a xtreme charger, looks like just what the doctor ordered for batteries that will be sitting a lot.

life begins when the kids leave home and the dog dies
Old 09-01-08, 07:57 AM
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This type of cut off, or any type for that matter, is harmless to your or any vehicle as it is equivalant to a battery disconnect. The only repercussion to this is that every computer on your vehicle that has memory functions will be reset each time you disconnect the power. Therefor requiring a relearn or manual reset, ie the radio. This is not a huge deal, but an inconvenience. The easiest thing to do is to install a battery maintainer. It is a small trickle charger that will charge the battery and maintain it while it is in storage. You can purchase these almost anywhere automotive parts are sold. I have one for my motorcycle. It comes with a quick connector that can be hooked straight to the battery and you simply plug it in when you store the vehicle, or you can use the alligator clips, your choice. Mine only cost around $40. I think I got it at Pep Boys, but I bought one for around the same price for my Mother in laws car that stays in storage in Florida for about 8 months out if the year at Sears.
Hope this helps ya,

P.S. If you decide to go with the battery disconnect then MOST DEFINATELY install it on the negative terminal. The negative terminal should always be the first to be removed and the last to be connected on todays computer controlled vehicles.

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