When trying to program a used Theft Deterrent Module on a GM
Received a vehicle (2011 Chevy Aveo) from another shop that had a complete used steering column replaced. (Vehicle was an attempted theft and the would be thief damaged the TDM (Theft deterrent module) along with various other items on the column. So the Shop opted for a used Column installation, The vehicle would not even crank over so at which point they requested a programming of the used TDM and keys to get the vehicle running again. I programmed the theft deterrent module and attempted to perform the Vehicle theft deterrent (Relearn & Link) however the Key (Relearn and Link) Would not complete. Tried a few different scan tools (Factory GM scanners) and no matter what was tried even turning the key on then hooking up scan tool nothing would learn the keys. At which point I realized that a NEW OEM replacement TDM (Theft deterrent module was going to have to be replaced) Making a call to the local dealer there was no local stock and I was going to have to push the vehicle outside in the snow and do the waiting game. I didn't feel like waiting this one out and the customer was really looking at getting the vehicle back ASAP. I then decided to Eeprom program the TDM (Theft deterrent module) I still had the original TDM that the housing was busted and some electronic components were damaged but the Eeprom device on the board was still in tact and certainly readable. I attempted to read the Target device, During the "In-Circuit" read It failed to gather any information on the eeprom. This is a common issue sometimes that must be overcome by removing (unsoldering) the Eeprom from the board in order to read the eeprom properly. Once the Eeprom was removed I was able to get a good dump/reading from the Eeprom device. I also noted that in the Eeprom dump or (read), the donor vin number never changed even though it should have when it said it programmed correctly to the vehicle ... All the more reason to believe a used TDM was not possible on this vehicle.. at least not through conventional methods.(Scan tools and SPS) I then used a key programming tool called a "Tango programmer" to get the key string data By examining the Eeprom dump and by using the "Tango" key programmer I was able to find the Key string data and vin number associated with both donor and original Eeprom's. At which time I was able to edit the Eeprom dump and add the necessary keys to one of the Eeprom's and write that edited dump back to the Eeprom then re-installed it (re-solder eeprom to board) to the good donor TDM. In the Pictures below you will be able to see where the Key string information is stored in that particular Eeprom and even where the Vin information is. This helps to edit the necessary address lines to change or add keys or vin numbers. I then re-installed the TDM (Theft deterrent module) around the ignition housing and now the vehicle will Crank and Start. Sometimes its methods like this that keep the mind and body so fascinated with the Automotive trade, I truly enjoy applying methods like this to speed things up and get these vehicle back on the road at the same time your learning the in's and outs of Electronic Automotive trade.
Thanks for sharing that info. I love my eeprom tools but I have to say that anymore I shy away from this type of work. I'm usually busy with easier higher paying jobs so I tend to push these off but I do enjoy the learning experience that comes along with eeprom work.
Hi Robert The nice part on learning these types of jobs really helps when new modules are obsolete. which then can turn into very profitable jobs.
Very interesting Kevin! - thanks for taking the time to share.
Fantastic write up Kevin! Way to save the day when parts are not available! With the GM strike and now the Corona virus interrupting the supply chain, it is good to have skills to work through this type of issue. As the back orders become more common, your skills will be more in demand.
Thanks for taking the time to show all of us what can be done and the magic behind the scene.
Great work! It truly is fascinating. Quick question as I understand zero of this. If all the data is in the eeprom is there a reason you cant just take the eeprom off the old and put it on the used? Thanks Chris
Great question, in this case you can swap the eeprom, however the one and only key they had for the vehicle was badly worn it also had a bend in the key shank with a small crack. I also informed the customer before starting that some Chevy Aveo's require two keys when attempting to program them in. (So the two keys were already sold with the expectation at the end of the job they would have two…
Thank you for sharing this information Kevin, I personally am planning to move into this type of work myself and could really benefit from this kind of posts and comments. It will be a profitable job when you can save thousands of dollars to your customers by not installing new units, but still make a profit from your expertise and knowledge. Good luck to you further on.
Now i been wondering if you can use the tango software without actually buying the tango. Like buy the software or do you have to buy the tango? Also great write up.
no sir you need to buy it to work with it. It isn't an every day tool for me but tango has NEVER let me down.