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ME3 - install question (yellow vs red battery cable)

1903 Views 16 Replies 4 Participants Last post by  fritzner
what is the difference between ACC +B (red) and Battery (yellow) on the ME3 wiring harness? I would guess the ACC +B is the positive battery terminal and the Battery is some sort of signal to let the unit know the car is on (and if so what signal do I tap for it)…??? I am trying to install this today so a quick response would be great - thanks
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Usually ACC means ACCessory i.e. switched (ignition) +12V.
So the Red goes to 13 - U14 ST DSP on the RNS-E harness and the yellow goes to the batterys positive(+) terminal?
I really want to install this today so please respond... thanks
ok, wtf... half the people on this forum have a ME3 installed and yet NO ONE knows what the difference is between the two wires? Throw me a freekin bone here, I dont want to mess it up and fry the DVD player. PLEASE RESPOND!
himnbandit said:
So the Red goes to 13 - U14 ST DSP on the RNS-E harness and the yellow goes to the batterys positive(+) terminal?
Sorry but most of us do have other things to do at the weekend!

That's my best guess - but it's only that. The chance of frying the DVD player by connecting these 2 wires the wrong way round is pretty near close to zero.
Sorry - this weekend is the only chance I will have to install it until Christmas. I just really want to get it working...
sorry i was out surfing all wknd.. i usually limit my time on the forum to when i am work :lol:

yes, as mentioned, ACC is typically for switched 12V (or pin 13).. the other one would be connected to 12V constant (though i put a switch on mine so i could "Y" in my iPod or PAC-MAN consul..

i also thought the the colors seem backwards.. but regardless they are both 12V, so there is no way to fry anything..

hope you got it all finished.. please share when you get a chance..
I tried connecting the yellow to the positive terminal of the battery then the red to the U14 on the RNS-E harness and it didnt work... I tried reversing it so the red was constant power and the yellow to the U14 and it works but you have to press the power on/off otherwise it does nothing. Are you sure the original way I did it is correct?
did you test for voltage at pin 13 (U14)??.. i know someone suggested using that U14 for ACC, but i dont recall anyone actually doing it (verifying it)..

i have the older style, 2-box 1417 -- so my wiring is different..

but ACC should be for ignition 12V and Battery should be for contant 12V..

do you want the DVD player to turn on when ever you turn on your car??.. seems like pressing the power button is not a bad thing..

good luck..
Its not turning it on when the car starts that I am worried about ... its forgetting to turn it off when I turn the car off. I sometimes dont drive for 3-4 days - that would leave me with a dead battery for sure.
Well... it only took 2 days to kill the battery. Sunday night when I drove it everything worked. I checked twice to make sure the ME3 was "off" (with the blue light on) and today my battery is completly dead. I love that the forum is able to help one another hack software upgrades and configure bluetooth kits but cant help a guy out with his ME3 install... half the people on here have them installed - why can't I get a straight answer? Obviously my setup is not working:

RED ME3 ACC cable into the straight power
Yellow ME3 Battery into U14 on the rns-e harness

I also tried the opposite and that did not seem to work either. With the current configuration I was able to get it to power on which was not the case with the original way I was instructed. I just want the ME3 to work and not drain my battery - I am sorry if I sound pissed, I just want to know what I am doing wrong?
himnbandit said:
RED ME3 ACC cable into the straight power
Yellow ME3 Battery into U14 on the rns-e harness
You need to connect the RED ME3 ACC cable to an ignition switched +12V. And since there isn't one of them available at the RNS-E connections that means running a new cable back to the ignition +12V - which IIRC is on one of the screw terminals near the steering column. It's been mentioned here befopre, so a search should find it.
sorry i can not help much.. my 1417 is different than your -- it is an older 2-box version..

1st, have you tested U14 (pin13) to see if you actually get 12V when the RNS-E is on and 0V when it is off??..

another thought is the RNS-E on shuts off after ~20mins or so..

U14 has been suggested, but i havent heard of anyone actually using it.. Dave says there isnt any 12V ign at the RNS-E..

i cant see why your battery would drain if the ME3 is off (ie. blue light is on)??..

you may need to find true 12V ign from the fuse block or just put a switch in (flip the switch whenever you are done watching)..

good luck..
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i found you cannot use pin 13 directly you need to use relay (its better anyhow as can handle any power drain just get correct relay)
Ok so:

RED ME3 ACC cable to an ignition switched +12V somewhere near the steering column and Yellow Battery can be ran straight to the battery? I already have a cable ran from the battery to the trunk for my amp/sub so I just tapped into that, is that a problem? Thank you for the responses.
yes that it is correct..

no problem to tap of the battery -> amp wire..

for others, you dont have run a wire from the battery for a DVD player - there are 12V constant near the steering column as well.. or splice in the the 12V to the RNS-E..
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