head unit not turning on, accepts cd but doesnt light up Options

[brianforster]

all the wires are plugged in the right spots and everything appears to be connected right.

does this mean my head unit is messed up?

or the factory 2 amps are messed up?


this is an aftermarket head unit, using the metra 70-8112 harness going through the factory amps.

please help , i jsut want cd capability

[Yobbe]

So you get no response from the headunit other then it eating and ejecting CDs ?

[brianforster]

exactly

i think the head unit is blown because i hooked it up directly to the battery and it did the same thing, so i guess i will try buying a new head unit

[Yobbe]

Sounds like the headunit is blown yeah... unless it needs power on some additional wire ... Have you checked the wiring scheme for the head unit ?

[brianforster]

nope its pretty old kenwood kdc-217

ill look it up right now

[3TST]

DON'T QUOTE ME ON THIS but
There are normally 2 power supply cables that need to be connected.
1 from the battery which is for memory functions (MEM)
2 from (I think) an ignition live circuit (IGN)
NOTE: MAKE SURE THESE WIRES HAVE IN-LINE FUSES.

Definitely look at the wiring diagram for your head unit.

EDIT: You'll have another 2 power cables as well.
1 for your AMP(s) and 1 for an electric antenna.
...and don't forget to EARTH real well.

This post has been edited by 3TST: Mar 18, 2004 - 8:49 PM

[Yobbe]

The KDC-217 manual has the following solution to what seams to be you problem (kinda):

Q: The power does not turn ON.
A: The fuse has blown. (Check fuses, replace and retry)
A: No ACC position on vehicle ignition. (Connect the same wire to the ignition as the battery wire.)

Q: Nothing happens when the buttons are pressed:
A: The computer chip in the unit is not functioning normally. Press the reset button on the unit (page 5).

The reset button should be just below the right end of the display

[Yobbe]

3TST is right i think ... The harness should supply two wires with power.

One that bypass the ignition and always have power on it (to keep the memory in the headunit) and ...

One that is powered when the ignition is on (to "start" the headunit).

[3TST]

I think the 2nd IGN power wire that goes to the ignition switch is connected to the live wire TO the ignition so that the head unit works with either the ignition on or off. If you see what I mean. BUT IT IS DEFINITELY INDEPENDENT OF THE MEM WIRE AND NOT CONNECTED DIRECTLY TO THE BATTERY.

Infact, now that I come to think about it, your cigarette lighter works with either the ignition on or off and has a live to it. I think I spliced in there.

I actually installed a Sony Xplod CDX-MP70 head unit, 2 amps, 4 speakers and 2 sub-woofers sometime ago using an aftermarket harness but unfortunately I don't have the diagrams in front of me.

If you can post wiring details (wire color, short name e.g. MEM and description) for both you're head unit and your aftermarket harness, I'll try and work it out from memory for you.

[brianforster]

ok the head unit has 3 wires that i know need to be connected to get to work

red wire to battery
yellow is mem wire
black (ground)



update: i wired the red and yellow wires together and touched it to POSITIVE of the battery and black to ground and the head unit turned on and worked

so i go to car and keep both the wires together, then i wire it to the yellow wire coming out of the harness and it blinked utnill i actually turned the car on then it stayed on and i was plugging in the preouts for the speakers and i started to smell smoke so i turned it all off.

now i cant even get it to do what i originally posted, i checked all the fuses...

i guess i must have blown something this time


this is so damn complicated

[Yobbe]

OK, time for me to sleep ... Looking forward to reading more in a few hours ... lol

[brianforster]

what could be the problem if hooking up all the wires yields nothing and I know the head unit isnt the problem and neither are the fuses


stock amps blowing? (that shouldnt have anything to do with the head unit powering on should it?)

im lost

[Burt]

try hooking the head unit up to the battery directly with the red and yellow wires

dont forget the ground

if it turns on then its not the head unit

if it turns out that your stock amps are fried and you cant afford a new 4 channel amp then i would recommend wiring each speaker to the head unit and ditch the Metra harness.

get some good 12 guage wire for the speakers too.

[brianforster]

but if the stock amps were blown the head unit would still be able to turn on wouldnt it?

[Burt]

yea

[Burt]

well actually if the power is running through the amps first then to the head unit and the amps are blown then the head unit could possibly not get any power..


i dont know how the wires run behind there but its definitely a possibility

[brianforster]

its not even getting that far

[Burt]

what do you mean its not getting that far?

[brianforster]

i hook all the wires up and i get absolutely nothign to the head unit

but if i hook them up to the battery directly, i get juice

it may be a bad ground or something, i will try it again tomorrow morning whne im less tired

[Burt]

i will brainstorm and post what i come up with before i go to bed