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Mark N
Mark N, ASE Certified Technician
Category: Car
Satisfied Customers: 200
Experience:  Saab Master Technician, GM Technician, 30 years experience.
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SAAB: to be present to start/run

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I have a 2003 9-3. The radio is dead-came from a different car and was not "married" ( or divorced from whatever it came out of). Q.1 Does the engine require a SAAB radio to be present to start/run? Q.2 If so, then the Saab radio/head unit must remain--somewhere. True? Q.3 What has been experience with after-market radios? Any recommendations? Q.4 OK,so what (estimate) do new radio and labor cost?

Hello and welcome!


First I need to know if this is a sedan or convertible. In 2003, these were two totally different animals.

Customer: replied 6 years ago.

Right-- neglected to include that. This is a Sport SEDAN so it is the first after the conversion to the GM architecture.

Hello again-
OK, first of all, we need to clarify what is meant by "radio". Sounds stupid, but the unit in the dash that has all of the radio controls on it isn't the actual radio unit. This is what Saab calls the Infotainment Control Unit (ICM). The actual radio is behind the dash, out of sight. All of the audio components are connected together on a fiber-optic network called the o-bus. If there's a break anywhere on the o-bus, no radio functions will work, and the turn signal sound, key chime, and warning sounds won't work either. If this is the case with your car, you need to find the break.


By far the most common cause is the amplifier that's mounted under the driver's seat. To be sure, have a competent Saab tech check it to determine the problem, as audio components can be pretty pricey for these cars, and it's worth a small diagnostic fee to be sure.


The car will run if any one of the audio components is disconnected, but I'm not 100% sure about the ICM. Not a lot of trouble with these, though, so that shouldn't be an issue.
I've never seen an aftermarket radio in these cars, probably due to the optical network I described above, so I can't comment on that.
It is possible to by-pass the radio, amp, etc, if the o-bus is by-passed also. Again, a Saab tech could do this fairly easily.


If any of this isn't clear, please feel free to write back. Thanks for checking in with us!

Mark N and other Car Specialists are ready to help you
Customer: replied 6 years ago.

Mark N--

Thanks that was most helpful--I'm beginning to understand the pricing more clearly--didn't realize but am not surprised that there are three units--the underseat, the ICM AND the 'radio' itself, hidden in/under the dash--not to mention the fiber optic. Knew it was there, but I don't think anyone has pointed a finger at it--yet.


Will need to check fiber optics--think it is alright, but turn signal sound might be a clue that the fiber cable is amiss.


ICM appears to have a bad on/off switch--but that is relatvely cheap--$110.90 according to my longtime dealer in Chicago.


Underseat amp is as I expected--roughly $1000--and I am told but have not confirmed that it is 'corroded' and that this is a common problem on 2003-2004's.


OK, just heard neither turn signal clicks or key chimes are working. With your help, looks like we are getting closer.


Thanks for your response. Have some investigation to do.


Bob C.



No problem, if you need any more info, check back.
Customer: replied 6 years ago.

Mark, thanks again.


Assuming your 'symptoms' are correct--and I have no reason to think otherwise--I have at minimum a bad fiber cable--no turn signal sound, no key chimes, no warning chimes, and of course the radio/stereo/disc is inoperative but at least the in-dash 6-disc appears to be getting power--loads but won't eject disc. BTW this is the middle unit--I think SAAB calls it a Premium 150 with 7 speakers.


My Significant Other (girlfriend--at my age!) found a 'repair' shop in White Plains..He was going to fit an aftermarket Kenwood, but it was so hokey that I stopped him. I am now doing his diagnostic work.


So the question is: how do I/we proceed? Clearly we need to start with the fiber cable, then diagnose the radio/amp/ICM and 'marry' it to the car (OK reverse order or simply replace). Question--how do I buy what I nned? Cable(o-bus) sold separately? Comes withe amp/receiver or what?


Let me know. Thanks again, Bob C.

The o-bus starts and ends at the ICM in the dash. It's one big loop that needs to remain unbroken or nothing on that loop works.


If you unplug any of the modules , you should see 2 orange fiber-optic cables. You should see red light coming from one of them. If you see light, then the circuit up to that point is ok. Here's how the light travels through the modules, in this order:


Starts at ICM
To the Onstar module under the rear package shelf (if it's still there)
These next three your car probably doesn't have installed, but I'll list them anyway.
DVD unit for Navigation
Rear CD changer
Amplifier 2 in the trunk
Then to Amplifier 1 under the driver's seat
Entertainment Head Unit (EHU) which is the radio behind the dash
CD player
Back to the ICM


Take the amp under the seat out and check for light at the connector(since it's the easiest one to get to). If you have it here, plug it back in and move to the EHU.
You can pull the CD player and EHU out of the dash by doing this:
Take the climate unit out of the dash (manual controls or automatic). Then you'll see the CD plyer and EHU mounted together on a bracket. On either side of the bracket are 2 metal clips that you push in towards the units, and get your hand behind it and pull both out together. This will allow access to the connectors. Unplug one at a time in the order listed above. When you get to a connector that doesn't show light, the problem is in the previous module or the cable between. Unplug the previous module and shine a flashlight into the end of the connector. You should see light at the other end of the cable. If you do, the cable's ok and the problem is in the module.


Hope this helps! Write back if you need more info.

Mark N and other Car Specialists are ready to help you
Customer: replied 6 years ago.

Mark N.--


Beautiful answer! Didn't realize the o-bus 'toured' most of the car. but your instructions are great. Suspect OnStar module is still there--I had the antenna repl w/ non-onstar version since this is still an analog unit, so on-star is irrelevant now. Other three options you cited are not installed, as you expected. May take 'til mid week next week not diagnose, but I will let you know what we find. Appreciate the help and the sound guidance.


Bob C.