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Discussion Starter #1
Hi, I have a 52 plate 147 2.0.

I fitted an Alpine head unit about a year ago and it worked very well and even got the alfa steering remotes to work.

I didnt secure my head unit in with screws as it was very tight round the back with all the wires and I just slotted it in. I wanted to try and move the wires around a bit this weekend and attempt to secure the stereo in place.
I removed the stereo and pushed it back in and it was working fine. I got into my car this morning and the stereo seems to power up and work perfectly but there is no sound from the speakers at all. I don't have a bose system.

However, I did install new front speakers at the weekend. The connections were clean and soldered on with no excess bare wire. They worked all weekend. It was on tuesday morning when I got into my car that no sound came out. When I turn the stereo on there is a funny click or pop that comes from the front left speaker. Would this be the stereos safety feature cutting the internal amp off because of a short somewhere? I'm going to have a look again tonight. I'm just wondering whether it is likely to be a loose ground connection or something loose in the back of the stereo as that is the only part of the system with cables all tight and crammed together.

Does anyone know which connection would be loose or have come out?

Also, I want to get the stereo to dim when my side lights are on. Does anyone know which alfa wire I will need to connect to get this to work? I know that it's the orange on from the stereo.
 

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AO Silver Member, 155 Lounge Winner 09
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firstly, check the setup menu to ensure the 'power IC' is 'on'. this is the inbuilt speaker amplifier which can be switched off. perhaps it reset when you unplugged the headunit.

could be worth hitting the 'reset' button anyway.

i figure the headunit is not muted for some reason (eg: audio interupt wire at the back shorting to ground); this would be displayed on the front. if the rest of the headunit works (display, lighting, etc), then presumably the powerwiring/ground is intact.

failing the above, there could be a short circuit or disconnection. indeed, a shorted speakerwire will disable the amplifier into protection mode. a short could occur in the doors (eg: speaker terminal touching metal door).

worth removing the headunit to double check all connections. if you have retained the ISO plugs, then ensure they are connected properly (these are like the alfa plugs).

it may be tedious, but you may be required to test each speaker individually, to see that they all work, and it may reveal which is faulty.

there is no dimmer wire in the original alfa plugs for the factory radio (except via the CANBUS wires which aren't suitable for the new headunit).

your car may have a spare/unused white plug tucked away with the stereo wiring. this can have an illumination wire (0V with side/headlights off, +12V when on). refer to the .pdf by TallPaul in the first post of his thread:
http://www.alfaowner.com/Forum/ice-and-blue-and-me/96560-alfa-gt-stereo-and-phone-connections.html

you will also find that the cigarette lighter has backlighting. however, from memory it only goes to +5V when the lights are on. this should still be enough to activate the dimming function on the headunit; if not, use the +5V to trigger a relay that controls a +12V supply.

:)
 

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I have the CDA-9857 which I guess is pretty similar and shiny_car has very good suggestions there.

I never installed any screws when fitting my unit, its just secured by the standard frame - I'm not even sure how you would be able to secure it any other way as its very tight behind the dash

Wish I could change my blue buttons to green at night to match the rest of the night lighting
 

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Discussion Starter #4
Thanks for the great reply shiny car.

I have checked that the internal IC is on.

Any idea where the reset button is located?

I took the stereo out last night and checked every cable. No wires are bare and touching and all cables have a good connection.

I think there is a spare white connector behind the stereo, Ill look into that and try and find a +12v supply.

I did fit new speakers over the weekend and I checked to make sure the connections were good before securing them. They were'nt great speakers though, they worked for the first 3 days and then werent working on the 4th day when I started my car.
One of the speakers makes a short sound when the stereo is powering up and then there is nothing. I cant explain the sound too well but its as though there could possibly be a problem with the speaker. Maybe blown or faulty and then the internal amp cuts out. Is this a possibility?

If I take the door card off again and unsolder the suspect speaker would my stereo work again if it was the speaker that was the problem?

If I require new speakers can anyone recommend any good component sets for the 147?
 

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Discussion Starter #5
Ive just had a look on the web and these are the speakers I fitted

In Phase XTC6 240W component speakers Reviews

I thought they would have been cheap seeing as I bought them from a mate for £20 new.

However, I didnt install the crossover or the tweeter as the tweeter was going to be a pain to fit anywhere. Does anyone have any good installation ideas for the 147 door. Nearly every bit of the panel is curved so its hard to flush mount!

Has anyone else tried these speakers?
 

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AO Silver Member, 155 Lounge Winner 09
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Any idea where the reset button is located?
refer to the manual. it should be on the front of the main unit, after you remove the detachable face.

Maybe blown or faulty and then the internal amp cuts out. Is this a possibility?

If I take the door card off again and unsolder the suspect speaker would my stereo work again if it was the speaker that was the problem?
yes, quite possible. a short circuit/blown speaker can 'take out' all the amplifier channels.

If I require new speakers can anyone recommend any good component sets for the 147?
yes, plenty. it depends on budget or what quality you're after.

I didnt install the crossover or the tweeter as the tweeter was going to be a pain to fit anywhere. Does anyone have any good installation ideas for the 147 door. Nearly every bit of the panel is curved so its hard to flush mount!
i haven't seen those speakers - not sold here in Oz.

it surprises me a bit, that people commonly only fit 'half' their set of component speakers (pretty common question here about whether you should/can do this)! it is like replacing your bald tyres with only two, and expecting great grip in the wet.

the 'woofer + tweeter + crossover' are a matched set. together, they are designed to sound good, with nice transition between midrange and treble, have the same power handling for the woofer/tweeter which is partly provided by the crossover, and importantly, ensure the impedence (ohm) of the set remains 4ohm across all frequencies.

perhaps your hybrid of 'new woofer + factory tweeter - proper crossover' has resulted in an impedence well below 4ohm. this can damage your headunit; let's hope you haven't fried it.

START AGAIN. remove the factory tweeters, and rewire everything:
*the speakerwires that originally connected to the factory door woofer can connect to the new crossovers (yellow factory plug is presumably already cut off, which is necessary to have bare wire)
*carefully observe polarity: hopefully you know which is POS/NEG speakerwires, otherwise everything can be out of phase (sounds bad)
*from the new crossover, run NEW speakerwire from the woofer output to your new woofer; run NEW speakerwire from the tweeter output to your new tweeter

you should be able to mount the new tweeter behind the factory tweeter grill after removing the original tweeter. you can make a metal bracket from some aluminium stripping to help secure it. unfortunately, aftermarket gear tends not to drop into position and needs some work. pretty normal. :)

until the speakers are all wired up properly, you cannot be certain what is causing your problem of no music. again, hopefully you have not damaged the internals of the headunit. alpine are pretty robust, and have good protection circuitry, so it should be ok.

:)
 

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Discussion Starter #7
Once again, excellent reply Shiny Car.

I guess I was just being lazy not installing the crossover and tweeter. I'll definitely have to install the new tweeter and crossover. I just have 2 more questions before I go ahead with this:

You say that I can use the wires that originally connected to the woofer to supply the new crossover and then presumably run a new pair from the neew crossover to the woofer and a new pair to the tweeter?
When I took the door panel off I saw what I thought was a very small, cheap looking factory crossover clipped to the door. Had 6 wires, 3 of what looked like + and 3 -. If this is the case and this is in fact the original crossover would I have to cut these wires and install the new crossover in its place?
Or did I get this wrong and the crossover is installed in the factory tweeter or somewhere? If this is the case, what you said makes sense to install the crossover from the full frequency range coming through to the woofer! (Hope I havent confused you by now)

My 2nd question is: Does anyone have an original wiring diagram stating the colour, polarity of the speaker wiring in an 02 Alfa 147? I don't have a multimeter to test the polarity, I know this is completely wrong but I was hoping that the wire with the darker colour or more of black on it was the negative!

The main thing that's worrying me about all this is that once I fitted just the woofers at the weekend, it was all working fine for 3 days and then just stopped working so I've got a fear that I've blown the stereo amp. I'm going to correctly fit the full component set on Sunday and hit the reset button and hope this resolves my problem. If this doesn't work I think my next and cheapest step will be turn off the internal amp and try a new external one?

Many thanks.
 

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AO Silver Member, 155 Lounge Winner 09
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You say that I can use the wires that originally connected to the woofer to supply the new crossover and then presumably run a new pair from the neew crossover to the woofer and a new pair to the tweeter?
When I took the door panel off I saw what I thought was a very small, cheap looking factory crossover clipped to the door. Had 6 wires, 3 of what looked like + and 3 -. If this is the case and this is in fact the original crossover would I have to cut these wires and install the new crossover in its place?
hmm. is there a chance your factory speakers have actually already been replaced with aftermarket ones?

normally, the factory system is very basic:
*fullrange signal enters door via set of speakerwires
*speakerwires divide into 2 branches, one for woofer + one for tweeter
*woofer receives fullrange signal; it relies on its 'natural rolloff' (ie: inability to play high frequencies like treble) and plays midrange downwards
*tweeter has small (generally small enough to be hidden) inline capacitor that functions as the most basic of highpass crossover filters (to filter out the midrange and below)

what you describe is pretty much like your new set of component speakers: xover box with a set of input terminals, plus woofer outputs, plus tweeter outputs (6 terminals; 3 each for POS/NEG connections).

regardless, you connect up your new set of component speakers similarly:
*ensure you have the fullrange/first set of speakerwires that have come into the door from the headunit: connect these to the 'input' terminals on the new xover
*(yes) run new speakerwire from the xover 'woofer output' to the woofer
*run new speakerwire from the xover 'tweeter output' to the tweeter

My 2nd question is: Does anyone have an original wiring diagram stating the colour, polarity of the speaker wiring in an 02 Alfa 147?
i'm unsure if the 147 differs to my GT, and whether it's dependent on model spec. my car had Bose. in the passenger door, the POS speakerwire was pink/blk, and the NEG was purple/blk. in the driver door, the POS was red/blk, and the NEG was white/blk.

The main thing that's worrying me about all this is that once I fitted just the woofers at the weekend, it was all working fine for 3 days and then just stopped working
chances are nothing is blown. but there is a short circuit or something with one of the speakers, causing the headunit to go into protection mode.

:)
 

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right this happend to me , on the top alpine units they have an option to turn off the speakers so you can just run the sound through the rca leads to an amp , off hand i cant remember the option to change it back and just hitting the reset botton does not sove the pronlem, do you have your owners manual have a look through if not pm me am i will look though for you
 

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AO Silver Member, 155 Lounge Winner 09
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that was suggested in my first reply. ;) the 'power IC' function.

:)
 

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Discussion Starter #11
Hi John 147. Thanks for trying to help but I have already looked at the power IC setting and it is definitely turned on.

I bought some new speaker cable and some solder this weekend and have booked Friday off work to fit my speakers along with crossovers properly. I'll report back on Friday evening to let you know if this works.

I looked at the spec for my speakers and they are 4ohms so will be pretty hard to drive and maybe without the correct crossover fitted this will cut out the internal amp.

I still dont understand why it would have been working ok for 3 days after installing though.

I'm really hoping that all becomes obvious when I remove the door panel again and one of the wires is shorting
 

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Discussion Starter #12
At last, I found the problem. Well.....I'm guessing at what the problem with me getting no sound was. I'm guessing the HU does a safety check on power-up. When I took the door card off I found that the connector into the tweeter wasn't properly connected. So, this is probably the reason the HU was shutting off the internal amp?!?!?!? It now works great!

This weekend I spent 8 hours fitting my speakers properly into just the drivers door! Yes..... A whole 8 hours! This is what I did:

found a place to mount the crossover in the door panel. This proved quite tricky as it is a large box! Superglue and zip ties worked a treat! I then prised off the silly little factory mounted tweeter and filed down the funny shaped plastic surround to make it flat. I pressed the new tweeter against the plastic hole surround which is exactly where the old tweeter was and then taped securely around it with electrical tape. It is now held very tightly in place. The new tweeter is over twice the size of the old one.

As I wanted to get the whole of the door finished in the one day I went and bought some dynamat and fitted it on the outer skin behind the speaker and then on quite a lot of the inner skin that the speaker is mounted on.

Also, behind the speaker I fitted some second skin acoustic wave diffuser which someone recommended to me.

The sound is now amazing from the one door and I think I will notice a huge difference when I get the other door done the same.

I would always recommend fitting the supplied crossover and tweeter with component kits!

Thanks for all your help guys. :thumbs:
 

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AO Silver Member, 155 Lounge Winner 09
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glad it's sorted. :)

however, i don't like the idea of using just electrical tape to secure the tweeter. maybe it's not very hot over there, but a single summer day in australia will cause the adhesive to soften, and the vibrations from driving around could be enough to cause the tweeter to become loose and rattle.

i would do a more permanent fix. or even 'hot glue' is more durable; otherwise silicone. but ideally screwed/bolted into position, say with a metal strap or mdf wood mount.

:)
 

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Discussion Starter #14
I was actually thinking today of how to make a better permanent fix for the tweeter. I was thinking about a metal strap over the top too. Im going to look more closely at some tape Ive seen that is supposedly as good as super glue and I think it might withstand the heat too.

Or does anyone know of a paste or glue the when applied will dry as a hard shell over the top of it? :confused:
 

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AO Silver Member, 155 Lounge Winner 09
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you may not need it 'too' permanent. ;) i've used silicone for various trims and stuff in car installations before. i'm not sure what brands/products you have over there, but a general purpose silicone should be fine. water- or acid-based shouldn't matter; the former is easier to clean up using a damp cloth.

in australia, i buy Selleys All Clear, which is a good general purpose product.

:)
 
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