whale508

Mike Wilson here with an audio question: Had my 1994 FD since... 1994. A standard model without CD player. Bought CD player from Mazda and installed it a year later. Flash forward to 2022 and now the CD player is not working. Disk cleaning is no help. I pulled it out and the AM/FM and cassette player produces no audio now. Plug in CD player and speakers come back to life. I know the audio worked fine when I bought the car without the CD player. Why is it now requiring the CD player be plugged in to allow audio from the AM/FM and cassette tape player. I can't find a pinout for the CD player.

Maybe a power reset would training the AM/FM unit to see that there is no CD player. Any help would be great.

Thanks Mike

DaleClark

iTrader: (55)

That's a good question. Unfortunately 99% of the FD's out there seem to have aftermarket head units at this point and I have very little experience with the stock stereo.

I'm hoping someone else can chime in on this!

Dale

whale508

Dale,
Thanks for the early morning reply. I have one more thing to try and then it might be time to "move on" and put the broken CD player back in to allow the radio/cassette to work. Hate to do that given all the effort getting that thing out.

Mike

Pete_89T2

iTrader: (4)

Hi Mike, don't have the answer to your question, but if you don't already have a copy, you should download the '94 Body Electrical Manual, available on this link:

http://foxed.ca/rx7manual/manuals/94...ric_manual.pdf

That's the best source of technical info & troubleshooting on the factory audio systems the car came with.

My best guess is that if the CD player was a dealer installed option, the CD installation may have involved a different wiring harness or an adapter kit to wire it all up to the factory connectors. Perhaps with the CD player now removed, the necessary connections get buggered up - so you'll need to figure out what was changed during the dealer's CD installation and undo that.

whale508

Pete,
Thanks for the reply. The CD unit was an OEM unit from Mazda and I did the install but it was in 1995 and memory fades. The CD unit has a single cable that mates to the radio/cassette unit with a round keyed connector. No adapter cables in between.
I have the 1994 Wiring Diagram Manual but it does not give any information about the CD player connection. Shows only the Bose and non Bose audio systems.
I will take a look at the manual you have referenced. I sure appreciate your help. I just now tried pulling the fuse for a while and then powering the radio back up without the CD unit hoping it might recognize no CD but still no audio out.
If I find something, I will post is.
Mike

DaleClark

iTrader: (55)

I would also check the dumb stuff - there's 2 connectors for the stereo, a ground, and an antenna cable. Make sure all the connections are snug. I think one of the connectors has most of the speaker connections on it so maybe if that one isn't snug you would have power but no sound.

Dale

j9fd3s

iTrader: (3)

i think there was a little plug that needs to go in place of the CD player? does that jog anyone's memory?

whale508

Thanks for the "plug" idea. The wiring manual posted is very good. A pin of the radio and the CD player is labeled MUTE. Hmmm? Trying to figure out if I need to make a jumper to B+ or ground and try that. That may be "the Plug". If it is jumper on the plug, it must be be either ground or B+ since there seem to be no other logic levels. I think this is progress..

Mike

Pete_89T2

iTrader: (4)

It doesn't jog my memory, but electrically that makes a lot of sense... Referring to page J1-6 in the '94 Body Electric Manual, you'll see that that 13pin DIN connector that goes between the AM/FM/Cassette head unit and the CD player has both input & output (LH & RH) audio channels assigned to the pins. Which most likely means that cars that lacked the CD player would have had a DIN plug there that jumped the input & output audio channels together when the CD player is absent (which would otherwise complete the circuit if it were present).

Based on schematic below, if I had lost the original DIN plug, I'd try jumping pins #1 & 2 together (LH audio in/out) and jump pins #3 & 4 together (RH audio in/out) on that 13 pin DIN connector and see if that solves the problem.

whale508

Thanks Pete. I will make some jumpers and give it a try.
Mike

whale508

Yahooo!! Time to celebrate. Jumpered pins 1 to 2 and 3 to 4 and left the Mute pin alone and there was sound. That is the trick. Thank you all for your help. Now just tidy up the jumpers, connect the antenna back and slide it all back in.
Thanks Guys.

Mike

Pete_89T2

iTrader: (4)

Cool, glad it worked!