Here are tips and guides of navigation unlock with a TECH 2 scan tool
Car: I have a 2011 Chevrolet Corvette ZR1 that came with OnStar and Xm radio.
Purpose: I would like to swap the radio for a Navigation unit but remain with the stock Denso style corvette navigation unit.
Reason for navigation unit unlock: I purchased a Denso unit that came from a 2008 ZO6 and it worked when I fist plugged it in but after unplugging it the “Theft Lock” appeared on the screen.
I tried looking on ebay for unlock services and checked with a couple Chevy dealers but have not found anyone that says they can unlock it.
How to unlock a navigation unit using Tech 2:
You need an Tech 2 test instrument to unlock it.
The Tech 2 programs the navigation to the VIN number of your car.
The nearest Chevy dealer in my area should charge me an insane price to unlock it so I bought an Tech 2 myself. I don’t think they knew how to do it so gave me an insane price so I should not come to them, they had the Tech 2 instrument.
It was done in about 3 minutes, because I never used the instrument before.
The GM” >GM radios are VIN” >VIN specific, so the unlock process involves clearing the old VIN # from the nav unit, and allowing it to accept your VIN#. As I said, this can be done by anyone who has access to a TECH II. All GM dealers should have them, and if they tell you they can’t unlock the radio, they are not telling you the truth. I went to my local Chevrolet dealer when I installed the nav unit in my 08 base. It’s about a 5 minute job, but they charged me a 1 hour minimum labor $130.
I copied the how to shown below from a fellow forum member.
Here is how to use the TECH II to put the Nav unit into relearn mode:
Connect TECH II to car and put the car into acc. mode
At the main screen, select diagnostics
At systems selection menu screen, select body
At the VIN indent screen select
Appropriate air conditioning
At the body screen, select Nav radio
At the radio screen, select special functions
At the special functions screen, select VIN relearn
At the VIN relearn screen, the scan tool will display, “do you want to clear the radio theft
To begin clearing, press the soft touch key on the top right of the scan tool. The TECH II will display “clearing theft in progress”
Once done, press exit on the TECH II and cycle the ignition
It’s done and the Nav unit will now marry to your car.
The last, Technically there is no “jailbreak” for for OEM” >OEM Navigation radios” >radios for Corvettes.
Once a GM radio is initialized for the first time it learns the VIN” >VIN# from the vehicle and writes it to a flash within the radio. From that point on any time the radio is powered on the VIN” >VIN stored in the flash is compared with the current car VIN” >VIN # and if they don’t match it throws up a TheftLock message (and/or lights” >lights a red LED” >LED depending on the radio).
All the technician is doing with the Tech2 is clearing the stored VIN# flash in the radio which causes the radio to relearn the new VIN # on next power-up.
My local GM service” >service dept. gave me the same speech when I asked about having TheftLock reset on a used OEM” >OEM radio(no guarantees resetting a used OEM” >OEM radio and no refund if they couldn’t reset it) which is why I purchased a clone Tech2 to clear it myself (as well as be able to reprogram fobs on my other GM vehicles) and never looked back. I have now done several resets and BCM configuration changes for several local Corvette” >Corvette owners free of charge (ok, sometimes I accepted cold beer) and will continue to do so for anyone who asks.
That being said I posted detailed screenshots of how you reset the TheftLock on a Navigation radio here to make it easier for other members to do their own resets.