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Right i have just fitted my Alpine 9813R HU.
But have a few quiries.
Basically i have the HU connected direct to the battery using an uprated cable. I also have the Ignition cable from the HU connect to the battery using the ISO standard connections.
The problem is if i undo the ignition cable from the iso connector the HU doesnt power up.
I would have thought the HU would of powered up regardless of the ignition cable being disconnected cause of the uprated cable supplying the power!
It needs both 12v memory AND 12v power leads to function. Basically, out the back of the hu, you should have 2 power wires, one constant 12v and 1 switchable via the ignition (or you can connect dirct to the battery like you have). If you want it to be permanently available, you must connect both of these wires to the battery.
So basically ur saying if one is not connect the HU wont work!
Icecavern
26-04-2004, 10:22
The red lead ( the one not connected to the battery) is an ignition feed. This tells the HU to switch on and off with the ignition. It's like that to stop you leaving it on and running the battery flat. This one still needs to be connected to the ISO block so that it takes the ingition feed from that. It's only used to switch the HU on and off so doesn't need upgrading like the battery feed.
Pete
I know that but i would of thought even without the ignition cable connected it would work.
As there is the uprated cable to the battery that should supply the power then?
Icecavern
26-04-2004, 15:01
No I think you miss-understand. The connection you have to the battery is there for the HU to draw it's power from. The ignition connector is simply there to only turn the HU on when the ignition is on. You could connect the ignition ( red ) cable to the feed you have coming from the battery as well, but then the HU would not power up and down with the ignition. The ignition connection is just a turn on/off signal basically
Pete
I think ive got you!
One question tho.
Would the HU power up if u have the ignition lead not connected?