View Full Version : Unofficial NAV XM module install problem 03 DTS

charles white
08-12-08, 02:53 PM
There seem to be a lot good gurus here for the “audio tech” to the DTS Nav units, and I wanted to know if I could ask you three possibly related questions. If you can take the time, I have below explained a complex sounding problem, you guys might be able to help me with.

1) I have a 2003 DTS with NAV, and 3 years ago I added a "very unofficial" GM Silverado truck XM module to the class-2 data harness connector for the XM wiring harness that already existed in my trunk. For the first 1.5 years I had the DTS, all the cad dealers kept telling me “a GM XM module you want was not an available as an aftermarket module for 03 DTSs …that I could buy” (even though the stereo HU NAV could do XM and the car was wired for it …there is a very long XM-licensing story for why this was the case at GM). However, I really wanted a clean factory installed look and good quality sound which the digital DTS bus could do, and they basically said that it did not exist (even though it was obvious that my DTS was set up to do so).

Well, I do not react well to “can’t”, especially when I know this really means “they won’t allow me to”.

Thus I searched a long time and I found a work around for my XM desire. I was informed back then (by a now lost GM expert) that an “unofficial GM XM box” would indeed work for an 03 DTS. I searched 1.5 years for the GM bulit XM box, and lo and behold I found it and it did work….that is most of time. It works great when it is recognized by the DTS NAV/data bus, and as I said it works great most of the time (75% of the time and with wonderful ultra-crisp/clean all digital audio input into the Bose 200+ watt NAV-HU I have , and with all the NAV screen controls properly working too…it even converted the previous AUX button on the NAV to show XM1and XM2 and shows all the song data on the NAV screen as well …all with a factory clean look:) sweet).

Note: While I do not have the exact GM Silverado XM box unit PN number I used at the time of this posting, I can get it from my files if needed by someone else (I believe then it was the same XM unit that the 03 Silverado truck used for “approved GM” post-purchase truck XM upgrades – and I was told back then that it could indeed handshake with the same data bus in the ’03 DTS).

The problem I have is that my ‘03 DTS data bus system intermittently ignores the XM unit (it shows the XM song/artist is playing but no sound is produced) about every third to fifth start and will not recognize or handshake with the XM unit again until I do four very cumbersome steps: a) cut the radio off, then b) cut the car off, then c) open a door and close it, and then d) restart the car. After that procedure (there may be other fixes too) it seems to reset and work again for another 3-5 starts. This reset procedure can also get real embarrassing to do, especially when my friends are in my sweet DTS ride !! I wish I had found this forum sooner, I might have solved this problem long ago.

2) Perhaps this XM glitch might even be what causes a trouble code every so often when I inspect and clear out DTC codes in the computer memory (it is just a plain-jane error code saying data bus error that relates to no specific module). I was told by someone I know that it might be because the system has not been Tech-II programmed/enabled at the dealer to know that the XM box is enabled and there. However, I could not go and get the Tech-II programming done while I still had a GM warranty, which just recently expired. As a result of that warranty expiration, I did recently explain and ask my local cad dealer “audio expert guy”, and he just looked very “dazed and confused” and stated “it’s not supposed to be an available option for your 03 DTS, your not supposed to have this, where did you get it, and it could void your warranty". Afterwards, I re-explained all the above to him again, I also reminded him the warranty was just now gone, and that is why I was asking him the question now. He was real nice and said he would not enter into GM system I had this installed, he was going to see what he could find out, but he had no idea what to do, was not very bright, and he never could find an answer of any value. As an example, the “expert” I was dealing with from this Houston cad dealer did not even know how to change the DIC to read “my name” versus “Driver#1”, which is very basic stuff.

Kind of difficult to do find a fix through “official Cadillac dealer expert”, especially since I can’t yet seem yet to locate a good Tech-II person at the cad dealers here in Houston. Could you guys steer me to an expert in Houston, or is there a way you guys know to have my computer/data bus in my ‘03 Cad DTS NAV system recognize this XM unit permanently where I do not have to cut everything off, stop, and open doors forever to reset?

3) Possibly related to this is that the XM channel audio settings loose their NAV audio setting memories too when I go from one XM channel to another and back (memory settings for tweaked bass, highs, midrange, effects, etc). This XM memory loss is happening 100% of the time, and I work around this by just having one favorite station per XM channel 1&2. In other words, the XM memory settings get amnesia and forget soon as you change the XM station within a channel.

From the sound of what I have been reading on this forum, you guys really seem to be a well informed.

Any ideas or things I should change, or is this a work-around something I need to deal with forever due to having a Silverado XM box installed in my 03 DTS?

I will thank you now in advance of any answer or insight you can help provide.

P.S. This is actually the very first board message question I have ever posted, and I am not sure how this works here. I can't PM to CadillacSts2003 or the others I see here because I just registered to this excellent website but if possible can someone email me (possibly even CadillacSts2003)? I sure would appreciate it! My name is Charles and my email address [edit: removed by admin for member's own safety].


08-12-08, 05:37 PM
its cuz that xm box is set up for the car it came from
you cannot use another xm unit from another car as they are vin encoded
go to the sticky buy the terk box and solve the problem for good

charles white
08-12-08, 07:18 PM

Thanks for the speedy reply. Below are my comments to your last post.

1) The unit was brand new and still in GM sealed box when I got it and never used, so no vin was yet used/memorized/exposed and mine was the first it saw when 1st connected to anything;
2) I actually spoke with several whom had done the exact same, the original GM guy had helped back then, and those other users have had no "memory loss"/amnesia problems like I had (and they all had 03 DTSs that used for XM - I called them back then to confirm)(actually recently I did hear that one was required to Tech 2 it get it to handshake with the bus);
3) The previous GM guy suggested then that I needed a tech 2 programming or other expert to solve this intermittant memory problem, but he also knew that I could not do this at Cad dealer for warranty reasons;
4) He then suggested to find a good Cad audio person or Tech 2 person/group locally to get that done, but he did not have any contact suggestions since he was from the New England area of USA;
5) I have yet to find one locally in Houston since I just moved here recently and do not have a network to work through);
6) I personally believe it is just a finicky DTS HU NAV and it needs to "told that a XM module is entered into the DTS system" (similar to what I have read about for other devices installed and explained on this Cad-Ownwers Forum website, such as with the battery removal needing re-learn/re-recognizing voice, XM and other data-bus modules).
7) Seems as though you guys know a lot ins and outs and maybe could help or suggest local Texas contacts (Cadillac or other).
8) If it works but has to reinitialize, it seems to me that buying another unit is not the answer and could even be repeated again at the cost of Turk unit I really can't afford right now.

Please note I am OK with now taking to a Cad dealer since my warranty is now expired, but the person I have found thus far is not as good, experienced, or networked as you guys. A suggested contact here would be good.

Smart people usually know the answer or know of another good smart doctor if a house call is needed.



08-12-08, 08:17 PM
the only thing i could try is to reflash the nav with the software disc which i have
once its reflashed it has no memory and then it relearns everything when key its 1st turned the next time
other than that its sounds like a data class issue like with the intermittent cd changer being dropped where you simply unplug the changer and plug it back in and your set for 3-4 months...

charles white
08-13-08, 12:38 AM
BTW: The GM XM module is part of a kit (antenna, module and connector wires) kit = GM part # 12498768 [called XM Radio Upgrade kit], and what I have is the XM module (GM part # 10333560 for just the XM module only). This XM module is "unofficially" supposed to work with my 03 Denso NAV HU (RPO U3R model NAV) that has the CD/Aux button (meaning the HU already has XM tuner capability and all that is needed is the right class 2 serial data line hookup to a rear XM interface unit with same pin out plug and antenna connections as the '03 Cad DTS I now have). Also, my Cad DTS already has the wiring harness OEM installed with mount location already prepared for OEM plug-in (for XM module location at driver side, back wheel well area, behind side grey trunk liner). The XM module is supposedly plug and play ready for this and is the exact size fit too for the trunk location my DTS has now. Supposedly, this GM part was being sold specifically and "officially" for the Chevy Avalache & Malibu and GM C/K full size trucks and SUVs, but was proven to "unofficially" work on the 03 DTS with Denso RPO HU U3R I have. Also, as was testified to me me personally by calling several other 03 DTS satisfied users, it has worked successfully for several other similar 03 DTS owners with same DTS HU as mine. However, I have not done a Tech 2 programming install yet (or I have missed some other tweak) and I have only the reset and lost memory problems (that I described in 1st post) that are intermittent every 4th-5th start.

charles white
08-13-08, 12:55 AM
Two added items.
1) Obviously I stand corrected on the 1st post stating Silverado. Apparently when I did open the files it was the Chevy Avalanch and GM models I listed in the Third post above.
2) I am aware there are 10s-100s of millions of GM part numbers, but do you think maybe they originally gave me the incorrect part numbers and that is the problem? Is there a way to cross check "unofficial uses", or should I just try and see if a memory wipe or tech 2 savvy person exists near me. Suggestions are welcomed if you think a tech 2 is warranted.



08-13-08, 02:37 AM
You probably need to get this done...

Oh, and I think there's only 3 (maybe only 2) different XM tuners. Does your nav not have a "Band" button? That is what you should be using to access XM.

Digital Radio Receiver Setup


The Digital Radio Receiver Setup option does not contain a submenu. Digital Radio Receiver Setup will configure the following systems:

• DTCs

• Class 2 radio messages

For the Digital Radio Receiver, complete the following procedure with the key in the ON position, use a scan tool in order to properly set up communication:

1. At the Main Menu screen, select Diagnostics.

2. At the Vehicle Identification screen, select the following options:

A. Model Year

B. Vehicle Line

3. At the System Selection Menu screen, select Body.

4. At the Vehicle Identification screen, select the following:

A. Platform Type

B. Body Type

5. At the Body screen, select Digital Radio Receiver.

6. Select Special Functions.

7. At the Special Functions screen, select DRR Setup.

charles white
08-13-08, 05:03 AM
Yes it does and I do that too now. I think the next step is figure out how to get a hold of someone who knows how to do Tech2 work. If I find someone, how would you answer the questions on "line, body, and platform". I will assume that I will have to spoon feed them. Any ideas on how to find people or companies that do Tech 2 programing work. Some suggestions on how to locate them would be very welcomed.

charles white
08-13-08, 05:33 AM

Thanks for the suggestion and info on the Tech2 form questions.

Cadillac Sts2003:

Is there a certain proceedure or sequence to disconnect and plug into the serial bus that might make a difference where the HU or serial bus could learn the xm is there. I did not think about it until I re-read your last post. I gather this cadillac computer is rather like a home computer or laptop, meaning you have to either:
1) tell it has hardware (i.e.tech 2 program), or
2) you can cut things on/off or plug them in the right sequence where they automatically get noticed by the system like a Windows system or like a wireless router reboot that needs the modem on first. Sequence and timming are perhaps crucial for PC hardware recognition. If you do right, you do not have to manually program the Systems hardware menu in Windows.

Ref 2) above for timing and cutting on/off items (i.e. as you said CadillacSTS2003 unplugging and plugging back in makes it work, and that is what I am essentially doing when I have to do my a to d steps above in my post #1, is there a majic process or sequence? There ought to be better reboot that sticks longer or a on/off sequence that can get this done without a Tech2 programming. Is there a on/off sequence that could avoid the Tech2 programming process where it would program itself to self recognize the xm hardware?

Or do I have to just bite the bullet and somehow find a good Tech2 person/service-company. Preferably not a dealership. Can you guys help me locate such a Tech2 person locally. Any ideas here would be welcomed and appreciated.

Thanks guys.

08-13-08, 09:51 AM
nope its pretty simple
go to your xm receiver wherever you mounted it and simply unplug it with the radio on
then plug it back in

CD Changer Inoperative - Icon Disappears from Radio Display - kw accessory audio Bose display intermittent U1Z proactive #PI00974A - (May 5, 2004)
CD Changer Inoperative - Icon Disappears from Radio Display


When servicing the vehicle with the VIN you entered, the following diagnosis might be helpful if the vehicle exhibits the described symptoms.

Panasonic class 2 CD changer is inoperative and icon does not display on radio. Customer may state that this happens approximately every 3 days. If they remove the CD magazine and reinstall it, the CD changer will work once again for another 3 days.

Engineering is currently working to resolve the concern. Some dealers have replaced both the radio and CD changer with no resolution.


Please follow this diagnosis process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed. If these steps do not resolve the condition, please contact GM TAC for further diagnostic assistance. This diagnostic approach was developed for the vehicle with the VIN you entered and should not be automatically be used for other vehicles with similar symptoms.

(2002-04 Cadillac Deville) and (2002-04 Cadillac Seville)

charles white
08-14-08, 02:01 AM
Hello all:

As an update, I have confirmed today that the XM module I had installed previously is indeed the correct one to use and its installed multi-wire plug-in conector has the correct pin-out connections that mate exactly with the DTS wire harness connector.

Just to make sure, I called the company that had sold me the unit and had them look up the wire pin-out up for the xm module I bought from them. They were quite confident that it should be plug&play to my exact 03 DTS HU. They even sent me the wiring diagram (and circuit board diagram) for the exact GM XM module part that I bought. I further checked that against my FSM pin-out for the existing OEM installed XM and connector and wiring harness I have in my 03 DTS. Pin for pin a perfect fit to the DTS harness connector. Ref the problems I am having with xm and NAV, they believed that the xm module could possibly be bad, but really doubted that would the case. Furthermore, even though I bought the unit from them over two years ago, they agreed to replace it for free if I do not solve this problem I am having. When I described the detailed problem info above on all the resets I need constantly, along with the memory loss for XM station settings, it was their belief I needed:
1) a Tech 2 programming (as you all have suggested), or
2) their xm module was bad and maybe need a new one, or
3) a new HU was needed (or as you suggested a less expensive wipe of the HU memory).
His belief agreed with yours on the xm un-plug/reset and tech2 programming would probably solve it, but what got their expert thinking was that it was his understanding that added memory setting loss problems I had are what he believed to be a NAV HU item and not the job of the xm module. Thus if the tech2 and hard un-plug/reset methods you have suggested do not work, the HU or the xm module could be at fault.

I guess I will try and attack the problem in the order of 1) then 2) then 3). I am presently scouring Houston to see if I can find an independent tech2 shop, have not found one yet (again, suggestions here are welcomed). Note: The cad dealer today said it would be a minimum $100 just to try and use their not-so-smart audio tech, and from what I have seen on you site that is a bit steep for a dull knife. I wonder if I should try the other cad dealers too?

The only other things I wonder about is there is any VIN issues you mentioned that could apply. I also confirmed today that the XM unit was indeed new when I got it.

If you have any more suggestions, I welcome them.


08-14-08, 02:33 AM
The XM memory settings are FOR SURE not stored in the HU. I have switched HUs and my presets for XM stayed the same.

If your XM module was not new it would read "XM THEFTLOCKED" on the display. They *can* be unlocked, but it takes someone who knows how to do it with the right interfaces.

08-14-08, 02:28 PM
according to ewill
the xms can NOT be unlocked

charles white
08-14-08, 09:48 PM
Sorry for the confusion CadillacSts2003, but the XM module I have is not locked nor has it ever been locked. When it works, it works quite well, just in a semi-crippled mode and in every 4th or 5th start of the car. I believe if it was locked, it would be bricked forever.

I am just trying to get out from under presently using a "Rube Goldberg" complex workaround reset/restart procedure. I think Cadillac DTS customers deserve promised functionality. My present solution works, but it is a bit of a ridiculous work around. Cars should not work like Windows 98. One should tweak automobiles to get better performance, not tweak to get already promised functionality. XM was promised by Cadillac for 03s and they have dodged responsibility.

Overall though, it looks like the suggested 1) unplug method and 2) Tech2 settings solution possibilities discussed in prior above posts are the most logical next steps.

At the moment, my DTS car is now at Yosemiti Park, but it will be back in Houston in a few days and I will be back at the work grindstone. If I can find a non-Cadillac Tech2 source, hopefully soon, I will try it and then and report back to this forum on the success or failure. I have already been making some calls on this but to no avail yet.

If solved for either a simpler reset work around or for a total fix via a system Tech2 reset, it looks like this would be a literal "bolt-on and plug&play" answer that all 03 DTSs (and possilby other caddies) that have been plagued from the start with a lack of a GM XM solution (which was also listed as a problem in many prior posts in this forum). A bolt-on and plug in solution here will also be much simpler than having to pull out dashboards and make wire harnesses to enable XM Direct systems work as they should. I will say, up until I just recently found this Cadillac owner forum, the XMDirect is and would have been a good and proven answer I would have used (but it was not available then). However, if easily fixed, the solution I am now using works more simply, and it will also actually provide a genuine GM module fix that can potentially help an owner's resale value in that uses actual genuine GM parts. (I intend to keep mine for a while, as I really like the overall Look and illuminated sport floating dash of the 03 DTS). You know, if a XMDirect solution had been there when I needed it several years back I might have used it then because I would have avoided paying GM for a part to solve their own problem they created. A company should not advertise an option for a product that is denied later to the customer.

However, by providing a solution to my problem today (that was shown to me by others after a lot of digging), setting it free on the internet, that uses a genuine GM part (with your guys applauded and appreciated suggestions and assistance of course), this could make a good XM alternative solution that can help others that want simple and literally plug-in answers.

Frankly, it also looks like GM/Cadillac could have provided this from the start, or at least leaked it after the XM license problems they had in the start of 03 (so I heard from the grapevine, ...funny how it effected 03 DTSs). That is why I listed the exact parts numbers earlier, so others could know exactly what to buy and install. I am an engineer and a physicist by training and own several companies, but not everyone else on thi forum has the skills ability to "build a wire harness" and "analyze an electronic schematics". Personally, I do not have the time for all this either. I just happen to be at the moment. However, it is kind of fun to solve tech problems (the engineer in me). I also would get a kick out of using GMs own part to solve their problem. I also wonder if it could somehow positively effect peoples warranty (where using an after market non-GM module add-on, it will kill it). I thought often in the past of just disconnecting the XM module while under the warranty period, but the inboard computers in caddies know all and store all. That is what caused my delay to seek the solution with a Tech2 (that would have voided my warranty). Furthermore, (before this forum, I was also mistaken and thought Cadillac was the only Tech2 sources to use. However, when one uses a proven genuine GM module, if someone indeed had a warranty problem where GM used the XM module as a means to skate around responsibility (which is NOT the case for me), I know a lot of attorneys that would take that on in asecond when GM was the source of the XM warranty offending part.

If the solution I am seeking works, it will illuminate that they had the answer all along. If the GM module provides a simple fix, seems as though they could have just avoided or eliminated the problem for us owners to start with. If it does not work, well I got to use XM for years now while they thought nobody with 03 DTSs had an answer to get around them (this is a long time period prior to the now XMDirect method).

Kind of the same way I feel about the NAV codes you guys struggled to find in (and successfully found and internet liberated...way to go ;)). This too could have been carefully leaked by them in a way where they still could have had the legal firewall they needed to avoid undue US litigation liability. The computer industry and other large markets do this a lot already. They serve their customers and protect themselves at the same time.

Anyway, I will stop venting now ;).

Bottom line, the help for the fix to my problem, thanks again. I believe it is going to be either a tech2 solution or bad XM module replace, my biggest hurdle is finding a independent Tech 2 shop that does not want a ridiculous $100 to $110 per hour fee that Cadillac seems to want. BTW, it is not so much the cost of that, but I also just do not like paying the same group whom may have willingly caused the problem (by not providing the part that would have solved the problem to start with). Kind of feels like extortion or paying the mafia for protection.

P.S. Still would enjoy it someone has suggestions that could help me quickly find and locate an INDEPENDENT Tech2 shop here in Houston.

Thanks again for the feedback and help.

I beginning to really like this forum stuff BTW. ;)

08-15-08, 02:18 AM
according to ewill
the xms can NOT be unlocked

I don't care what ewill says. I know someone who has done it with the proper equipment. The Tech2 will *not* do this. You need the know-how and a interface from http://www.dgtech.com/

He's also switched GMT800 TNRs from Lux to non-lux for me which supposedly "can't be done".

charles white
08-15-08, 03:09 AM

charles white
08-15-08, 03:24 AM
Guys, does this make a difference to what we have discussed on the XM problems I am having and the Tech2 possible fix?

1) TSB No.: 01662NHTSA No.: 10007248TSB Date: January 1, 2004Date Added to File: June 4, 2004 Failing Component:
Equipment:Electrical:Radio/Tape Deck/Cd Etc. Summary:
Xm error on a radio display.

2) (I got this somewhere off the net...maybe even off this forum) "XM may not be an option in tech2 menu for 2003 models.
so what they have to do is,when they do vehicle and year selection in Tech2, they may need to select CTS and 2005 or higher as a year built. then they can see XM option. that's what I've been told by GM (off the record), and I used it, and it always worked"

Cliff, considering your suggestion on the Tech2 settings sheet you provided in a prior post above, will you help me know how to fill in those blanks so I can tell/show a Tech2 person exactly what to input or type, and also will item 2) immediately above effect that?

08-15-08, 11:01 AM
1 doesnt apply its stating the xm posting and registering a fault
yours is dropping off the menu completely like the cd changer bulletin i posted

08-17-08, 09:20 PM
Anything can be done with the "right equipment".
Not many people have it though.
The ones we get from our service center are unlocked to be installed, but once powered up they VIN learn and I can do nothing.
I don't have the tools to do it, and I seriously doubt many forum members do.
I didn't read this whole thing so I can't say much about the rest.

08-18-08, 02:42 AM
Cliff, considering your suggestion on the Tech2 settings sheet you provided in a prior post above, will you help me know how to fill in those blanks so I can tell/show a Tech2 person exactly what to input or type, and also will item 2) immediately above effect that?

That should be fairly standard stuff for anyone who knows the Tech 2.

I can't remember the order of the selections right at the moment, but it's usually fairly easy. The platform/body type if i remember is the 4th and 5th digits of the VIN (K/F).