OK so I just bought this 1988 780 Bertone It is to say the least a very amazing car that needs a lot of work. I tried putting in new rear speakers and for some reason they are not working? I have factory radio in and guess by the speakers i pulled out they had to be factory as well. The speakers were not working to begin with and only one door speaker is working. I dont know where all the fuses are i know there is one fuse box in the center right in front of the gear shifter but i dont know where the rest are if that could be the problem also i have no idea what size speakers to replace the doors with and what kind of cdplayer i should install any help would be great.

 

I'm not sure about the '89, but the 91's had an amplifier in the trunk, under the driver's side shelf, next to that speaker. It has a fuse inline, tucked beneath the carpet close to the power antenna. Its signal comes via a DIN cable from the head unit.

Stock front speakers were 5.25"; you have about 2.5" in depth. Previous owners may have changed that, however. You won't know until you get the grilles off.

Cd players, not sure. The factory units were typically made by Alpine; my 1991 had a Volvo-branded Alpine CD changer in the trunk, but good luck finding a 20-year old Alpine CD changer that still works. And I'm not even sure the 1989's had provision to attach one. You may just have to buy an aftermarket CD/head unit, and start from scratch. Crutchfield has lots of head units, and can offer some assistance (limited, as it was a rare car).

Cheers, bt

 

Some times the volume ***** internally in the radio go bad and only allow certain speakers to work unless you mess with the ****. Other times it is to far gone to make them work.

 

Ok so far i pulled out the radio and looked at it apparently some one has messed with it before cause i had one bare wire which i got taped now and i pulled one of my door panels off and found my drivers side door wasnt hooked up i still have no idea why the rear speakers are not working but i think i am going to rewire the speakers as sson as i change out the head unit

 

IIRC, I think your car has not one but two amplifiers -- did you spot one in the trunk for your rear speakers? The one for the front speakers is up above the driver's knees somewhere. Does it have an EQ unit under the radio as well?

Cheers, bt