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Car stereo won't work!

Hi ! I just bought a Pioneer stereo player for my Fiat Grande Punto 2009 , I plug in the ISO adapter but it doesn’t power on . What do I have to do ?

Thanks !

New or Used ?

Well… You need to look into the adapter that you are using and make sure that you have

12vdc Constant power feeding the Yellow wire of radio
12Vdc Ignition switched power feeding the Red wire of radio
Ground feeding the Black wire of the radio

You also need a good fuse on the radio body itself…if they still locate the fuse in the back of the radio on your model. Sometimes the fuses are on both the yellow and the red inside of square black boxes inline on each wire…but usually the fuse is simply installed in the radios back side…it varies.

But those are the mandatory needed ingredients to make that radio power up. Verify that the adapter you are using is supplying the radio side with what I listed above… Sometimes the adapter plug gets the wire arrangement incorrect…or sometimes leaves a wire unconnected that needs a connection.

You need to verify and check… A digital volt meter would be your friend in this instance.

I wrote the wire color/purpose chart from memory, those colors and what they need to provide have been standard procedure for well over 20 yrs now in Radio Land. Time for some wire verification.

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And where did you get the adapter from? I usually recommend that people get the Crutchfield adapters. They’re matched to your car and your stereo, so it’s pretty foolproof, and I’ve never had one arrive screwed up.

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The black and yellow are connected but the red one it’s not… somebody told me that Fiat cars have this problem and that I need to connect a wire to the hazard lights or something like that… but I don’t wanna do that…

Used , does that make any sense ?

Some manufactures don’t use a switched ignition power wire to the radio, the ignition on/off signal is sent over the BUS. If that is the case you will need to add the switched ignition power wire for the radio to work.

Well for your application… You need those 3 wires hooked to their appropriate sources.

The wire color map and what they need is still correct in my prior post.

As a test… you can wire the red to the yellow…and the radio will turn on or be able to turn on if it is healthy that is.

However in that configuration the radio will not shut off with the key…it will be able to be left on…or turned on without using the ignition key.

You need a switched source of 12Vdc for the red wire…Going to the hazard switch would only gain you another constant 12vdc source… you need a switched one. You can tap your fuse box if you must but it really shouldn’t have to resort to that… I’m sure there are sources available.

Note: If you don’t know what you are doing (be honest) you might want to consider a pro installation. Especially if you need to tap into an existing wire or power source (without breaking that source wire etc…) I’ve seen people do amazing things in the radio installation realm… (amazingly BAD things). Be careful please. Dont burn your vehicle to the ground…or the house it might be parked inside…that sorta thing.

How to do that ? Therr isn’t an adapter that can do that ? Thank you !!

I assume you are not in the US so your wiring may be different than what people see here. Why not call a local stereo shop and see what they charge to wire this correctly and avoid a possible shorting out or fire.

You’re correct , I’m from Romania ( Europe ) , but our local audio shop only sell items… they do not repair something… for that you have to find an electrician or go to the local Fiat Car Dealer . Either options will involve some time and money… I thought it’s a simple solution :confused:

Technically it is a simple solution… but I suppose that depends on your perspective and experience level.

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Did you see and hear it working before you bought it ?

I had it on my other car , it works !

When faced with a similar situation, I tapped into the positive wire to the accessory socket (“cigarette lighter”) that turned on and off with the key.