03-early 04 CTS non nav head unit works as a code reader for all 03-07 CTS's and 04-07 CTS-V's

I had a stock early version disc changer from my CTS that I could pull all the codes from using the method in the FAQS. I upgraded to Nav later on(from an 05 0r 06), but the code reader part in Faqs didn't work. So it got me thinking it wasn't a change in the car but rather the head units for 2003/ early 04 CTS non Navigation System.
So having the stock changer left from my CTS when I sold it, I got the dealer to unlock the theft lock on it while installed in my V, not sure if it work or not.
Taking out the old head unit and pluging in the CTS changer takes like 2 Min.
Unlocking the theft lock cost 50.00. Sure enough it pulls the codes, I pulled a wheel sensor off just to F* with my stabilty system and throw a code. It pulled it and I was able to clear it.
The CTS code reader pulls every code from the car, not just engine codes, but body codes, chassis codes, and network codes.
You can find the base CTS head units on ebay for around 100.00 or less, most people think they are relatively worthless, not knowing about the code reader, the whole reason I held on to it. You should be able to tell if it's an early model because they have a cassette player in them.
To pull codes for the 03-early 04 head units, follow the instructions in the Faqs.

Press and hold the F1 and F6 buttons simultaneously; the Driver Infomation Center (DIC) will clear and a menu will appear to read and clear DTCs. (Need to confirm this method)


Anytime I have any problem I can just swap out head units, then pull and clear codes. Should serve me well untill I get a tuner.

damn great info tommy...i just bought an OEM Nav unit and i was wondering about that as well...

i got a can obd2 reader, but it did not work on my 03 cts... so i have to use the factory deck. the reader i got has worked on every car i have tried(chrysler, honda, chevy,gmc, ford, jaguar) except my cts... kinda sucks.
so im not sure what the reader requirements are but i would like to know. my suggustion is to buy one someone else has had success with on a caddy.
i can try it on my cts again and see if it can read that it has no codes, i think it just said it was unable to connect.
the one i have is just a cheap-o from crappy tire got it on sale for $50 or so but it has some good features, you can plug into a laptop. and other than it not connecting last time on the cts, it has served me well.

The problem with or one problems with obd2 scan tools is they only will tell you pcm/ecm codes, which is good if you have engine problems, but they don't usually tell you chassis codes for brakes, network codes or body codes. Hooking up a 03-04 non-nav cts head unit it will pull all of them.

Hey Tommy,

Have you thought about swapping the mother board from one radio to the other? I have two radios as well. Though neither one of them has a cd changer. But try it, and let us know how it works out. What I mean by the mother board, is the main board that you plug the car into. Take apart the radios and swap just that part. It should work, then once you have the radio with the cd changer and the "older" mother board. You should be able to use the F1 and F6 method.

KOT

this is the one i have, and i just noticed it only pulls P codes i think..... kinda not happy... i think im going to sell it and dump the 250 on a good one.... but my 03 the headunit pulls the codes fine, its just for my truck and friends cars.

http://www.canadiantire.ca/AST/browse/4/Auto/AutoTools/AutoCodeReaders/PRD~0251099P/OBD%2BCar%2BReader.jsp

Hey Tommy,

Have you thought about swapping the mother board from one radio to the other? I have two radios as well. Though neither one of them has a cd changer. But try it, and let us know how it works out. What I mean by the mother board, is the main board that you plug the car into. Take apart the radios and swap just that part. It should work, then once you have the radio with the cd changer and the "older" mother board. You should be able to use the F1 and F6 method.

KOT

Ya I'm sure you could swap two motherboards between two different changer head units. You could also just change faceplates if you want an old changer for obd and still have the black faceplate for the newer years.
The thing is this will work for those with factory nav units, not sure about swapping motherboards for that, also there are no f1 f6 buttons on a nav.
It's a little more work than plugging in an obd scan tool, but it really doesn't take much time once you've done it a couple times.

this is the one i have, and i just noticed it only pulls P codes i think..... kinda not happy... i think im going to sell it and dump the 250 on a good one.... but my 03 the headunit pulls the codes fine, its just for my truck and friends cars.

http://www.canadiantire.ca/AST/browse/4/Auto/AutoTools/AutoCodeReaders/PRD~0251099P/OBD%2BCar%2BReader.jsp

Ya i had one of those too, I took it back. They are ok for engine problems, but I wanted something with all the other codes too.
You may find a good unit that will pull abs brake codes from the ebc module, but without having a tech2 I doubt you find something as good as our head unit for a fraction of the cost.

There was another thread with other obd tools, one of them was bluetooth to laptop which I think sounds kinda cool.

I'm actually looking at getting a new truck for winter, haven't decided if I'm going to go bran new in which case I won't need 1 but if I go used ill be looking for a good scan tool.
Starting to consider a 2010 GMC Terrain blacked out.

There is a Gm Enhanced Software package available for these Guys:

Obd2 Scanner (http://www.carplugs.com/obd2scantool.html)

It gives your access to ABS, SRS and special powertrain codes.

If you have to send them email.

There is a Gm Enhanced Software package available for these Guys:

Obd2 Scanner (http://www.carplugs.com/obd2scantool.html)

It gives your access to ABS, SRS and special powertrain codes.

If you have to send them email.
That's sweet, I'd invest in something like that. Just have to buy a laptop to go with it :)
Nevermind they have a bluetooth model too.

There is a Gm Enhanced Software package available for these Guys:

Obd2 Scanner (http://www.carplugs.com/obd2scantool.html)

It gives your access to ABS, SRS and special powertrain codes.

If you have to send them email.

have you bought one of these yet? i think this would be a great investment for sure if it is what it says it is...