Problems on HU install

[Cronk152]

I'm installing an Aftermarket Head Unit (sony CDX-M3DI) in my 01 grand am and i've encountered some problems. after wiring it all up it turns on but when i play a CD no sound comes out of any speakers. The display graphics tell me the deck is reading the CD. I checked the voltage at a speaker output of the deck and there seems to be a small ac voltage. And the deck will sometimes shut off when i'm moving it around. and slight movements will turn it back on. I taped up all looses ends and can see no way it's grounding. I bought a Peripheral wiring harness (GMCO).

It's really bugging me and my friend who is helping me, anyone with experince please help.

[Bjornboy81]

Do you have the Monsoon system?

Make sure the remote turn on wire from the radio is connected to the appropriate wire. If it's not the built in amps won't turn on, and hence, no sound.

Under FAQ's there's a wiring diagram for the audio systems, check there if you don't have it, to see what wire it is. :)

Good luck.

[Cronk152]

Ya, got it fixed, thanks for the info. I still haven't found out about the shutting off yet.

But thanx again

[Bjornboy81]

np. :)

As far as the shutting off...how did you connect the harnesses, butt connectors, solder,? I always solder the wires together and then tape them and I've never had a problem. :)

[Cronk152]

strip about an inch, twist, fold back parallel to the wire and tape. My friend installed stereo's and thats how he always did it. And I can't ask him cuz I moved for stupid school.

But it dosen't reset the deck so It must be the ACC power, it can't be grounding i've checked everything numerous times. I just thought of this so I'm gonna go check. Think it might be the wiring harness?

[Bjornboy81]

you should at least have butt connectors in there...twisting and taping isn't gonna make it. If it were shorting to ground you'd be blowing a fuse. I'm guessing it's not making a good connection...it could be the harness itself too, but probably the connection.

[Cronk152]

pshhhhh, all my other decks were just fine. But thanks again.

[Bjornboy81]

I'm an electrical engineer so I'm a firm believer in good strong connections...sorry force of habit to overkill. :P

[ephiny526]

if you don't wanna go through all that trouble, walmart sells these twist connector things. you put one end of the wire in the tube, twist, put the other wire in the other end of the tube, twist, and you're all done. just a thought if you don't want to do the soldering thing.

[nineteen88ga]

Solder & tape, solder & tape, solder & tape.

I've come across on more then one occasion pins being loose in the harness. Chances are it's probably that, if not what kind of voltage do you have going to the radio? Too low of voltage can cause the unit to shut off and turn back on as could a bad ground.

[Cronk152]

Originally posted by nineteen88ga
Solder & tape, solder & tape, solder & tape.

I've come across on more then one occasion pins being loose in the harness. Chances are it's probably that, if not what kind of voltage do you have going to the radio? Too low of voltage can cause the unit to shut off and turn back on as could a bad ground.

How can you fix a loose pin? ANd i just used the power that was going to the factory deck. But i don't think it's that because it dosen't shut off if i turn it up, more if i jiggle stuff and push it in and out of it's cage.

And ever after switching the deck i have a noise problem. Actually i'll seach first then get back to you.

[MantaGreen97]

Originally posted by Bjornboy81
I'm an electrical engineer so I'm a firm believer in good strong connections...sorry force of habit to overkill. :P

You don't even have to be an engineer to know this. I don't understand why he's insisting on this "tape & twist" sillyness. No certified installer would ever do something so foolish.

Cronk152, As people have said and regardless of whether it is causing your problem or not, either use butt connector crimps, connectable crimps or solder/tape or better yet solder/heat shrink.

Twisting and taping wires is simply asking for trouble and never a recommended method for connecting any electrical wires anywhere. I don't know where/when/how your friend installed stereos but I hope it wasn't professionally! If his idea of installing a HU involves twisting and taping wires, then surely he doesn't have an MECP certification.

It does sound like your wiring is the cause of the problem. Barring that, there may be a problem with the HU itself, but you can't really know that until you do the connections properly!

[Cronk152]

About the noise, searched and searched and nothing.

It's at low volumes, sounds like white noise. When I turn it up it sounds good, and with further eq adustments will be perfect.

My subs and amp aren't in yet, I want to solve this problem first.

And another thing, i can only turn my HU up 1/4 of the way before it gets ear-splitting loud.



Ok, so why is it so bad to twist and tape? it's not like its under tension of anything. and as long as the connections good.

Holy Man i'm gonna hear it, i can just feel it.


P.S. my friend worked for FutureShop. I'd imagine you'd have to have some certification or something but i have no idea.

[MantaGreen97]

Well nowadays at FS you do require at least MECP bronze before you can get hired as a mobile electronics installer, but back a few years ago you didn't.

The problem with twising and taping is multi-fold. For starters, it isn't a reliable connection. When the wires move around (as in when you push the HU back into the dash, or when the car moves around hits bumps, etc.) they can cause intermittent opens which is obviously not good. From movement and over time, things can get disconnected. Even if it works fine right away, perhaps a year down the road something gets disconnected and then you have to pull out the stereo again and find/deal with the problem.

Another reason is that it isn't safe. You could have wires touch that could either just blow the fuse or they could damage either the car's circuitry or the head unit. For example, if two of the speaker wires touch, that's pretty much the end of your internal amp in the HU, or even the entire HU can get damaged in similar fashion. So you saved yourself $5 in crimps or solder and a few extra minutes to do things right but now you've got a $500 HU that's broken. Worst case scenario you can even cause an electrical fire behind the dash.

Now if you want to see if the problem is somewhere other than the wiring before you do crimping or soldering you can, but you have to make sure everything is connected right. Then try to move the HU, holding the wires so they aren't causing the problem and shake the HU gently to see if there is something inside it causing the intermittent fault. If you rule that out, I'd then go forward to do the connections properly and then install it in the dash properly (so it is secured properly in a proper kit) and then drive around.

If you're still getting the HU cutting out over bumps, etc. then we can go from there but I'm thinking you're going to find the problem in the above steps, before you get to here.

If you have a Monsoon amp, that is likely why you can't turn the volume up very much on the HU. If you've left the Monsoon amp connected, you're going to have to either feed it a signal from the RCA outs of the head units (and you'd probably have to wire up an RCA-to-bare-wire connection yourself) or use the speaker-level outputs and a Line Output Converter. The Monsoon amp is looking for a low-level input, not a high-level (which would be what the speaker outputs on the HU will be giving).

[Cronk152]

New info:

I just went out anf F'ed with it some more and have this to tell.
I'm more confused, after it cuts out it takes a few seconds to come back on no matter if i move wires or not. So it's not just a simple loose power connection. And the buttons on one side of my deck cut out. Problems interconnected? not sure.

And it's not like i go over a bump and it quits. Just barely moving it around will shut it down. I don't want to install it correctly then see if it dosen't work because it might be harming something. Plus i lost those butterknives that let you take the deck out of the cage.

This sucks.