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Zilla Hairball 1 ignition switch, can it be constant on?

1391 Views 2 Replies 3 Participants Last post by  EVfun
I have rewired my car to use the factory ignition key to start and turn on accessory power. It works but it is difficult to get the timing correct to activate the contactor. If I get my 'start' off the acc power, the contactor hits every time. I know there should be 'key on/engine off' power but really that is used in ICE cars.

Has anyone else applied a constant 12V power to the controller successfully? The wiring diagram for the hairball 1 just states it is a switch, just like acc power, but doesn't mention if it is momentary. is the car in question. I have had an issue when the contactor seems to just open (no power to motor) under very light load, even after the precharger light goes out. Could the two be related? The previous owner had an on button and a momentary ignition switch wired into the dash but I like to use factory stuff :)

Thoughts? Suggestions?
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You may have figured this out already, I have 12 volts controlling a relay running to 12 volts to the Hairball, this also energizes the negative contactor on my system... What is important to be sure the 12v does not go to zero when you continue to the start position on the ignition switch. I had to look at the car manual to find the 12v that does not "break" when the ignition is turned to the "start" position. I used the wire that ran to the solenoid to the started for the "start" connection to the hairball.

I hope this helps...

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Mo hit one important point. You cannot loose key power when you apply start power.

If you have a second contactor installed in the pack negative wire you must have that on before you apply start power. The start input cannot be connected to the key input if you have a negative side contactor because it will not have pulled in before start input sees power.

You cannot loose power to the SLI wire at any time and after it is first powered and you need to wait a second or two before powering the start line (if the hairball sees power on start before the hairball is computer is booted it will remain off and set an error code.) With a single contactor system start can be connected to the key input (but not the SLI input because then start would have power before key.) In my buggy start and key are tied together. My Datsun was set up with a separate start wire.
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