Thread: 3.5mm aux input for Delco Stereo

All-

Have been going through pretty much the same headache as mickstan on this...have a 99 Chevy S10 with the factory Delco head (AM/FM/CD player instead of the tape deck).

Am not ready to shell out the 70+$ for some of these 3rd party hardware solutions, but rather than dig into the guts of my radio, am looking to find out some info on the 9-pin connector on the back that's used to connect with aux inputs. Does anyone have any idea of the pinout for the connector?

Appreciate the help.

Originally Posted by AFMac30

All-

Have been going through pretty much the same headache as mickstan on this...have a 99 Chevy S10 with the factory Delco head (AM/FM/CD player instead of the tape deck).

Am not ready to shell out the 70+$ for some of these 3rd party hardware solutions, but rather than dig into the guts of my radio, am looking to find out some info on the 9-pin connector on the back that's used to connect with aux inputs. Does anyone have any idea of the pinout for the connector?

Appreciate the help.

I found a pinout on this site once but lost it. HOWEVER....the 9 pin connector is a serial port, meaning that you would have to have a control module talking to the radio to convince it that it's connected to a delco cd changer. Unless you're a computer engineer, you're gonna have to either buy the aftermarket cable or the delco cd changer.

Originally Posted by johndeereboy

I found a pinout on this site once but lost it. HOWEVER....the 9 pin connector is a serial port, meaning that you would have to have a control module talking to the radio to convince it that it's connected to a delco cd changer. Unless you're a computer engineer, you're gonna have to either buy the aftermarket cable or the delco cd changer.

What about the remote tape deck that was an option with this model radio...wasn't that interfaced through the same port? I've found some other folks who have built up a casette deck emulator, that basically fools the system into thinking there is a viable aux source, and opens up the input...have to believe that is modifiable in some way shape or form. Problem is these other methods involve direct work on the internal radio PCBs, and I was looking for the least intrusive method.

Im glad to finally see that others are doing what im trying to do and im not crazy. Anyway this is the starting point for a whole slew of radio modifications that i want to add to my 96' grand prix delco radio.

The thing is i DONT want to insert a cassette every time it switches to line in. i want to push a button and make it switch to line in. in part because i want to and in part because i cant get the tape to work anymore Anyway there are tons of wires going from the control board to the mainboard in the radio. I have found the line in ports after the preamp(if you put b4 preamp sounds like crap!). It was actually pretty easy. now the hard part is getting the thing to think there is a cassette inserted when there isnt. For this there are two switches that get hit when the cassette is inserted and then there is another switch with four inputs that turns, it connects to a gear which is turned once the cassette is inserted, and fully inserted. I have tried tons of stuff and i cant get it to think a cassette is inserted it always starts to play the cassette then says E19 and goes back to radio.

I have heard of other people making the am the line in which may be more easy (at this point). If i was doing this again i would have done it different, because now i cant get the values of certain things while they are in working operation.

anyway once i have done this i also wish to put a usb charger in the stereo i plan on hooking the usb charger and the aux in port (headphone jack) to the door where the cassette is inserted. And later on i want to put a PIC 16f877a inside that will control the lcd and output other information to it at regular intervals, kind of like a interface with the car's computer.

I am a CSENG student at UH. Anyway first step is first, i want to make the aux in port work. Does anyone have any ideas ?

I did the same thing on my radio (which looks exactly like the picture in the start of the thread). I have a Delco radio with cassette player in my 1993 Saturn. I opened it up and saw the same 5 wire cable from the cassette to the control board.


[FONT=Courier New] orange = right audio channel
white = left audio channel
red = 12v supply to the cassette unit
brown = select tape as input when shorted to +12V (red wire)
red/white = select radio as input when shorted to +12V (red wire)

The red/white wire appears to suck a bit of current, while the brown one doesn't. But If you use a SPDT switch with the red in the center, and brown and red/white on each end, this should let you have a radio/aux in switch.

You need to run a 6th wire for ground. Since the cassette must use the chassis as ground, I don't see a problem with that.

You shouldn't have to cut any wires. I found that it worked fine with the existing cassette circuit connected, although you may want to disconnect it if you aren't using it.

In addition, I found the left/right channel signals from the radio board (top board) to the control board. It is along the 8 wire ribbon cable. Unfortunately, I can't tell you which is pin "1", but the audio is on pins 5 and 6 counting from the back.

i have a 98 blazer and was looking to do this for *****s n giggles before i found the components i wanted to use for my carpc (or truckputer) setup. from everywhere i asked for info on this, it looked to be easily done with the 80's early 90's delco's since the amp board is seperate from the other boards. i took my blazers delco apart to see how this was designed. and its all in one board now. so it was very difficult. i have the aux tape deck. took that apart and rigged it to play aux input. it was tricky dealing with the switch that opens the circuit. after i got everything figured out and the aux to work, i realized upon testing it that there was a problem. the input was not apmlified.

upon trying to put everything back together to stock and use a tape adapter, it didnt operate correctly. it was recognizing there was a tape in the unit (when there accualy wasnt) and it would electronically act like it ejected the tape and go to radio. i couldnt figure out what i had done wrong. i think it may have been some little optical sensor on the bottom side of the mechanicals that i may have misaligned. i ordered a replacement off ebay and scrapped the original. i have the parts lying around somewhere.

i was trying to bypass having to buy that aux input made for my exact model radio. but my attempt failed. horribly haha.

i could not locate any diagrams or schematics for my aux tape deck. so it looked as if it was a no go. i had made posts in pennoks fiero forum, and whichever s10 forums are popular. and the 11+1 V forum. didnt find much of what i was looking for.

After finishing this project, I'm not sure it was worth it. The audio quality has less "hiss" than using the tape adapter, but the treble is noticebly less and the bass is way too much. I'm guessing that the audio amplifier is designed for tape input and only tape input. I think it is compensating for typical tape frequency response.

Yes mine tuned out horrible also, for some reason none of the buttons on the radio worked when i put it back together, i now have a computer speaker amp and a homemade usb charger in place of my delco radio.

Hi i am making a stereo system out of a delco radio from a 94 chevy very similer to yours, I was wondering if you could tell or show me where the wires go on the back for power, speakers, clock etc. if not thanks anyway.