I've heard of stories that the surges from the touching of the battery cables together can destroy sensitive electronics. It's common to see people run a motor and fumble with the jumper cables at the same time. This is an accident waiting to happen. What is the best way to protect car electronics such as the car's computer or the auto alarms from voltage spikes from the accidental shorting of the battery jumper cables without using a fuse?
Thanks
Sam,
A fuse won't do what you desire to do. Fuses are for over-current protection and what you need is a couple of diodes to install on both your +positive and -negative battery connections.
Here is a model that ciuld work for you. You might be able to buy these from ALLIED ELECTRONICS.
DieInterim
The best way to avoid that problem is to follow the usually detailed instructions in the owners manual. The manual for both of my cars has detailed information about how to jumper a battery, how to connect and disconnect battery terminals, etc.
Follow the car manufacturer's procedure for jump starting. Typically, you separate the cables - clamp the red positive to positive, and start the helper car motor, then clamp the black one to the negative battery post of the helper car, and clamp it to some piece of metal that's connected to the car chassis, like where the negative cable on the dead car bolts to the engine block; then rev the helper car for a while, to put _some_ charge on the dead one, and it should start right up. Then, remove the cables in the reverse order that you hooked them up.
Do _NOT_ try this without an actual battery in the car, however. That _will_ give you destructive surges as soon as you take the battery out of the circuit.
Good Luck! Rich
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