Line input (aux-in) for music player using telephone input

[nordwulf]

This tutorial describes how to add line input (or aux-in) to the head unit of a Saab 9-5 using the telephone input on the circuit board. It is the same method as posted on this Lithuanian website: SAAB 9-5 audio EN | Sand

I found some information that was missing and a few things that were not immediately clear so here is another tutorial using the same method. The head unit in my 2005 Saab 9-5 was also a little bit different.

The on/off switch for activating the telephone input is optional because the radio will mute as soon as it detects a signal on the aux input from a music player or other device. By using the telephone activation on the head unit with the switch, there will be a little bit less noise because there is a faint radio sound when you use the automatic mute. If your music player doesn't provide a high audio volume, the on/off switch will be more beneficial so the head unit volume will not have be turned up as much. The Telephone-in volume on the head unit can be adjusted separately from the other audio.

Audio quality is very good and similar to the CD player. Audio can be adjusted with the Bass and Treble controls on the head unit There is some light white noise when no music is playing but you will only notice with low music volume on your music player and when the car is stationary.

Parts needed:

Audio cable with at least one female or male 3.5 mm connector
Toggle switch
Electrical cable (about 2 feet)

Tools needed:

Soldering iron
Philips screw drivers (small)

Time estimate: 1 - 2 hours

Difficulty: It is easy to do but you must be comfortable with soldering electronics.



Instructions:

Remove the head unit from the dash by using removal tools. Knitting needles or nails should also work.



Remove 4 bolts from the face plate (2 on each side). Gently lift up the plastic tabs with your fingers and remove the face plate.





Lift up the top of the head unit so you get access to the CD player. Remove the 4 screws. Having a magnetic screw driver will be very helpful to remove some of the bolts.



Unplug the white ribbon cable from the main board by pulling it straight up. Remove the white plastic protector that keeps the ribbon cable in place. Lift up the CD player unit and put aside.



Remove the 3 bolts of the CD player tray and put the tray aside.



Remove the 4 bolts of the tape player unit, lift it up and put aside. There is no ribbon cable to detach.



Remove 2 bolts of the small upper part of the main chassis and put this aside.



Remove the screw and unplug the ribbon cable from the main board. Lift out the connector and small circuit board. This is the part where the on/off switch will be attached to.



The arrow on the right points to Ground, the other to the connection that switches the head unit to Telephone mode.



I only had another audio cable laying around but you can use regular electrical wire as well. This cable will attach to the on/off switch that I mounted in a switch blank next to the seat heater controls on the dash. More about that later.



Remove 3 bolts on the main board. Bent back the 2 tabs with needle nose pliers that keep the board in place at the front (lower arrows)





Lift out the main board and turn over.



The lower 2 arrows point to the line in for left/right audio signals, the upper arrow to the ground connection.



There are different kinds of cables but there should be 2 wires (left and right audio) and a ground shield wire. When you solder the red and white as shown in the picture, left/right audio (balance) will be working like it should. Use some electrical tape for the exposed ground wire after soldering.



Re-install the main board on the chassis and route the wire as shown in the picture.



Re-install the connector piece and make sure to plug in the ribbon cable on the main board.



I drilled a hole in the metal upper piece. There is a large open space in the cage where the head unit slides into and this was the best place for the wires to go.





Re-assemble the tape player, upper tray and CD player and attach the face plate.



That wasn't too bad, was it? It may appear complicated at first but it really isn't that difficult to do. Make sure to route the audio cable through the back of the unit before you solder to the main board.

The only thing left to do is to install and connect the on/off switch. I used a small switch I bought at an electronics store (RadioShack) but I imagine you can get these at many different places. I used one of the switch blanks next to the seat heater controls and removed all plastic parts inside that blank with a rotary tool. This is just one solution.

Another solution is to use a female end for the audio cable and use a switch blank to install. You can then use another audio cable to connect your music player.





I routed the audio cable like this but there are several other ways to do this. I am planning to get a console mounted iPod holder and this is the best place for the cable.



When you activate the switch, Telephone appears in the SID. The start input volume of the Telephone in can be set by turning on the head unit while holding down the Band button on the head unit. Use the Seek button to toggle to the Telephone volume and adjust.

[Rognmoe]

Does the 2004 have this same feature?

[nordwulf]

This should work on all AS2 and AS3 head units MY98-05. Some older ones may have different boards and tape player inside but the main board should have the same connections.

I have been using it for a while now and still sounds fantastic.

[Burnsside42]

Looks like a lot of work - but very neat at the same. Good solution for those who don't have an ipod my saab adapter. WHICH I need to install in the 9-3 still from our late 9-5. Hope it's compatible. lol

[Rognmoe]

I'll have to borrow my brother-in-law's soldering iron and do this one. I'm sick of wearing out cassette adapters.

[kenship]

THKS a LOT!

I just read the original thread on the Lithuanian website and this guide provides even more instructions.

In your guide you solder the shield to a GRD point instead of scrapping off the greens and solder the shield to the plate. Does it apply on all head units?

And to Rognmoe: I'm 100% like you, borrowed soldering iron from brother-in-law, and got sick of the tape adapter. LOL!

Thanks again!

[nordwulf]

In your guide you solder the shield to a GRD point instead of scrapping off the greens and solder the shield to the plate. Does it apply on all head units?

The head unit on the other website looks like it is an older one but it also has that GND pin. It just looks a lot easier to use instead of scraping off the protective layer on the larger part of the board.

[kenship]

Correct! Mine has the same years as yours and hopefully I can follow your guide 100%.

BTW, I read some of your other posts on other projects. Have you tried remove the plastic trim above the glove box?

[nordwulf]

BTW, I read some of your other posts on other projects. Have you tried remove the plastic trim above the glove box?

Not sure what trim you're referring to. Inside the glovebox?

[kenship]

I meant the plastic trim around the centre and the 2 front speakers, need to gain access to fix some squeaks.