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No ACC power to new HU


New Member
October 16, 2004
Reaction score
City, State
Portland, OR
Year, Model & Trim Level
'97 Sport 4WD
I just pulled out my eclipse head unit and put in a new Alpine 9827 with the KCA-420i iPod control unit. Got the new stuff from Crutchfield. The eclipse was prof installed and had an adaptor that took the output to line level and then into the factory harness to the amp. I abandoned that and put in the amp bypass harness and the power harness supplied by Crutchfield.

The problem that I am having is that I don't seem to be getting ACC power to the HU. It will not power on when the key is on ACC-- only the ON position. The factory harness has continuous (memory) power, radio (ignition) power, chassis ground, illumination power, and radio ground. The crutchfield power harness connects to all of them except radio ground. I think that there is one other optional connection on the factory harness that neither the harness that was installed with the eclipse nor the new power harness use.

I get 12v at the cont power lead off the factory harness and I get it through the aftermarket harness at least to the inline fuse. The ignition power is dead on OFF and ACC but 12v at ON.

So, it would seem that the problem is on the car side rather than the HU side. I would think that I should be getting 12v on the ignition lead when the key is on ACC. The eclipse worked fine on ACC, so this is a new problem. I pulled two fuses while I was working on the car. I think they were fuses 17 and 29. 17 is the cigar lighter-- and 29 is at least one of the radio fuses. None of the other fuses in the fuse panel that I didn't remove seem to be blown although I haven't physically removed them all-- just the ones that have "audio" in their description. I also looked in the power distribution box under the hood and nothing was blown.

Does anyone know if there is an inline fuse somewhere that just controls ACC power, or some way that I can check to see if ACC power is really out? Thanks in advance for any suggestions.

The iPod control adaptor is pretty cool, by the way. My only complaint is that the interface cables come out on opposite (long) sides of the unit making it harder to find a place for it. I put it in the glove box for now.

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Just grab the acc. power from somewhere else. The power windows, and wipers run in acc. in the Explorers I believe. The fuses don't always say what they do, so you may want to test them all. There is no saying what the installer used for the acc power on the eclipse.

The prof installer definitely used the same power as I am trying to use as he wired into the factory harness. Do the power windows work on ACC? I don't think they do... I am going to go over all the fuses again.

I called Crutchfield's technical service and the guy basically said this is normal-- He said maybe the eclipse didn't rely on the switched power the same way the alpine does. That didn't make any sense to me, but what do I know. I pulled and checked every fuse in the fuse box. Nothing blown. Power windows and wipers do not work on ACC. Anybody know what else should so I can test to see if something is actually blown? The crutchfield guy recommended I tap power off something else (I guess the cigar lighter is the natural candidate.) I am not too happy with that solution as I don't want to have to remember to turn the HU off every time I get out of the car.

Can anyone else with an Alpine HU confirm that it does/doesn't work on ACC? (I just don't believe that guy) Thanks.

I have the same head unit, and it needs the acc.

My windows, and wipers both work with the key turned back. The cigar lighter has constant power.

Thanks. I'm sure that I will be able to track it down.


I pulled everything out, checked all my connections, and put it all back together again. Now everything works fine. I didn't see anything, but I must have had a short or something.