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Possible to clear TheftLock before removal?

7177 Views 18 Replies 5 Participants Last post by  ponyboyt
I have a BOSE head unit from a 99 going into a 97. Ive seen this done before, and im looking to dodge the "$100 whether it works or not" dealer charge. Can i clear the theft lock from the 99 before i remove the radio? (have keys and power).

Otherwise, i do know someone with a Tech II that is not a dealer. He thinks he cant do it, but can he? It should just be somewhere in body options -> clear VIN once the stereo is installed in the 97???

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Ponyboyt check you PM (ah crap I just noticed the "t" and I sent a PM to ponyboy). You (or who ever is ponyboy) have all the answers in there but since is no secret matter here is for everybody who needs it:

1. BOSE/Base HUs from '96+ are OBDII ('96 and older are OBDI).
2. BOSE HU from '96 and '97 have only Radio* and Tape + provision for 12 disk CD Changer. '98+ BOSE HU have RDS Radio, Tape, CD slot and provision for 6 and/or 12 Disk CD changer. *All domestic '96-'97 BOSE HU have non RDS radio. I have seen a '97 BOSE (tape only) export (Germany) BOSE HU with RDS radio.
3. BOSE HU of any year is not compatible with base HU and the other way around so if you are planing to swap between base and BOSE stop reading it won't work (trust me, forget about it!).
4. OBDI and OBDII HU (base or BOSE) are NOT interchangeable so if you have a '95 and older car you cannot upgrade (again stop reading is not going to work!)
5. ANY '96-'97 BOSE Cadillac (except '97+ Catera) can be retrofitted with a '98-'00 BOSE HU
6. You can also install a '96-'97 BOSE HU in a '98+ car (except Catera). I don't know why would you want that but it works and no VIN clear is required (is truly plug and play).
7. 5 and 6 (including VIN comment) applies also to base HU but consider 3 (can't swap between base and BOSE period).
8. '98+ HU (BOSE ore base) includes Theftlock. You cannot just swap a Theftlock HU between two cars* unless the VIN is blanked. *The cars can be ANY year '96+ (again we are NOT discussing Catera).
9. In the '96-'97 Seville, '96-'99 Deville and '96-'02 Eldorado the HU compares the VIN with the PCM, in the '98-'03 Seville and '00-'04 Deville the HU (same HU as in similar year Eldorado) compares the VIN with the DIM.
10. The "compare" VIN is post "Read VIN" command. Any '96+ Cadillac supports this "Read VIN" command.
11. A brand new* Theftlock enabled HU (i.e. '98+ model) has the VIN blank before installing it in the car. *Re-flashing the firmware in the HU = brand new HU. Unfortunately I don't know anybody having the firmware nor how to re-flash it (so forget about this idea, there is no battery in the non NAV BOSE HU, the firmware is written in the control chip RAM, non-volatile memory).
12. A HU with blank VIN accepts ANY VIN and locks on it. So at the plant you can put any HU in any car. But once connected to the data bus it locks* on that car VIN. As long as you have a brand new '98+ - never installed in a car - HU you can put it in any '96+ Cadillac (no VIN blanking required). *The theftlocked HU startup sequence is:
a) Send Read VIN command
b) Read reply (within a timeout period). If no reply jump to h)
c) If stored VIN is not blank jump to e)
d) Store received VIN
e) Compare stored VIN with received VIN, if match jump to g)
f) Post "THEFTLOCK ENABLED" message on the screen, issue Theftlock code (Bxxxx), jump to h)
g) Continue with the audio startup procedure (read driver's settings, select proper source, volume level, EQ settings, DSP...)
h) Read clock from PCM, enable audio mixer and chime circuit.
13. A '98+ BOSE HU always initiate the startup sequence when connected to power, or immediately after "Clear VIN" command, so it locks immediately on the VIN of the car where is installed.
14. A used HU has a VIN stored, to blank the VIN, the HU needs to be connected to a car data bus. This is done with a TechII tool witch address the HU with the command "Clear stored VIN". The TechII works with any OBDII car, you need to set up your car before using it to control various modules in the car. The most convenient way to set up the car in the TechII is based on VIN. This will set up the TechII to expect all the specifics (options) of that car. You can also set up manually the tool selecting year, model, options (but is the long way around and is prone to "setup" errors). Either way you set up the tool (refereed as build your car options into the TechII) VIN or manual you specify the year. TechII knows that a '96-'97 car has no Theftlock enabled HU thus IT WILL NOT PROVIDE YOU THE OPTION TO CLEAR VIN. But if you are smart you know that to blank (clean) the VIN the TechII communicates ONLY with the HU. So when you setup/build your car in the TechII you select '98+ for the year (i.e. either provide a VIN of a '98+ car or you manually select model/year...). This is where 99% of the technicians don't understand and will tell you it "doesn't work" (they build a '96 or '97 car in the TechII and then they try to communicate with a '98+ HU). Just think for a moment is not too difficult to understand :bighead:.
15. BOSE sound system includes in addition to the HU a RIM (for the '96-'97 Seville, '96-'99 Deville, '96-'02 Eldorado and individual speaker amplifiers) or an Amplifier (kind of a RIM+Individual amplifiers in the same case for the '98-'03 Seville and '00-'04 Deville).
16. Cars with RIM have one power antenna AM/FM (not related with the fact that it has a RIM, just coincidence). Cars with Amplifier have glass integrated antennas (one AM and one FM). The '98+ HU provides a "FM band select signal" in addition to the "Power antenna control". These cars have a separate "antenna" module powered by the "Power antenna control" wire while the "FM band select signal" is used to switch between AM and FM antenna. The cars with power antenna don't use the "FM band select signal".
17. A '96-'97 RIM is 100% compatible with a '98+ car (although the P# is different). Swapping a RIM (if for some reason you need to) does NOT require any VIN blanking. Swapping a PCM or a DIM in a car with a theftlocked HU requires reprogramming the VIN in the VIN in the new PCM or DIM (NOT in the HU).
18. If you need (according to 1 to 16) to clear your VIN, you need a TechII. A GM dealer will have one but 99% of the dealers will send you for a walk if you ask this to be done in a '96 or '97 car (they just don't know better). The charge for this (~3 min procedure) is between $0 to $100 (but 90% is around $50).
19. In order to perform a VIN blank to a dealer you are obligated to show a legal proof of replacement HU provenience. The paperwork should specify the seller contact information and the donor vehicle VIN. The dealer is NOT suppose to perform this procedure if is not convinced the replacement HU is purchased legal. The donor vehicle VIN is NOT actually required in the process but is required for the dealer to cross check the donor vehicle owner against the HU seller (should be the same person).

Here is the proof a '97 Seville STS with a '99 Eldorado HU.

To O.P. I haven't forgot about you, still planning to visit your cars but I am kind of in South Africa right now for the next 2 weeks, I will return shortly to Canada only to leave for a couple of weeks for US, so count on my visit late April.
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I guess you can see it that way having enough lawyers pleading on the subject.
But in a strict engineering way is just a "clear VIN" command. It triggers the HU to store ("learn") the VIN but not directly, but as a consequence of the command.
OK for those of you dreaming to the "style" of the '96-'97 Seville, '96-'99 Deville and '96-'02 Eldorado center console wood trim I have one thing to say, the style is given from the shape (and wood pattern). Since the '97 and older is more stylish than 98+ (let's talk Seville) then the shape must be different. And YES I can confirm that indeed the shape is different. The older wood trim is almost same width at the back and significantly narrower in front (toward the ash tray). The old trim is almost rectangular (hence front width is about the same as back width) while the '98 + starts narrow (equal with with the old trim) at the back but expands toward the front (like a trapeze). It is longer than the old trim and is also thinner. The "wood" is more symbolic than actual solid wood (like on the old trim) and I have to say the quality is a bit shabby. Even though is longer and most of the time wider, yest is lighter partially because of the thickness and largely because the plastic around the shifter is not attached to the trim (as in the older style).

For those of you dreaming to put a older style wood trim in a '98+ car forget about it, you will have big gaps, the clips are not the same nor in the same position, the shifter plastic opening is different. For those of you who are dreaming the other way, put a new trim in the old is possible but MAJOR fabrication is involved. The only reason you want that is to get the zig-zag shifter pattern and the wood shifter knob. Honestly I don't care for any of the two, although is damn high maintenance that leather "cobra style" shifter knob, a wood shifter will be forever.
In order to get the zig zag pattern you need to replace the WHOLE shifter assembly in the shifter console. The metal cage/bracket/structure thing that accommodates the shifter movement consists of two halves (top/bottom) witch are riveted together.
The zig zag thing is more a matter of a style, only the first movement to the right (out of parking) is actually with a purpose. What ever the shifter knob button does on the older style translates in movement to the right of the shifter for the new style. So pressing the button or moving the shifter to the right is the same thing (release the shifter).
You have to keep the bottom of the shifter metal structure/frame and find a way to bolt the top part of the new style (including all the moving parts).
The extension where the PRND321 light bulb is mounted needs to be cut and bulb relocated. There is a wave guide underneath the PRND321 plastic that has to be modified to work with the new position of the light bulb and the interlock cable is not compatible with the new setup so some changes are to be done there too. Adapting the new style wood trim to fit the old style center console (i.e. trimming it) is the easy part.

To O.P. ponyboyt, are you also ponyboy or I have to PM ponyboy to explain I set him a message that was meant for somebody else?
AND KEEP ANY car that is in my color as I want stuff...I am returning soon but for short and I am gone again....keep the cars until late April. Actually even in June I suppose to be gone but I have May (so far that I know).
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