Infinity Headunit No sound

I was given a Infinity radio from a friend. I bought a Metra 71-7001 plug for it, hooked it up, entered the code from the Mitsubishi code card she gave me with the radio. BUT no sound! I check everything and the headunit will go to AM/FM stations and even play a tape, but no sound. One person told me that I need the amp that goes with it. HUH? The metra plug does direct hook up? What have I done wrong??? I am having a hard believing I need an amp, because then why would anyone need a anti-theft code for if it's useless without its amp??? It has a 14pin socket for power/spkrs, a 6 pin din socket for amp?? and CD change socket 16 pin????. Someone please help. For the record the headunit is not hot at all, she just replaced it with a alpine CD unit and she does not like stuff lying around.

Does your car have speakers?  What car is it?  Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.

But of course ,sir. That is how I knew that the radio was not putting out any sound. I also went and grabed a spkr from my surround sound system to make sure that it just wasn't the car spkrs. I also double checked every connection and any other basic stuff, so I would not waste all of you fine gentlemens time and knowledge when it could have been something easy to fix. That, I feel,  would be stupid of myself......

Some of the infinity systems have external amplifiers on the back of the speaker itself. This might have been the case with the car or truck you took the head-unit from.

The 71-7001 harness plugs into the OEM radio.  You must need a harness that will adapt your new radio to your car.Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.

actually the infinity radios produce normal output, they change the EQing of the music floor, but you should be able to power it up and use it... i would suspect that one of the plugs on the back ( quite likely the 6 pin DIN ) was actually used for a processor or EQ unit and that when unused should have a shorting plug in it...this bridges the audio out / audio in pins.....Kevin Gerry

Certified Electronics Technician

MECP First Class Installer

Owner/Installer

Classic Car Audio

since 1979