Originally Posted by
sosxfire
I believe (correct me if I'm wrong) Viper-666 is referring to a transponder bypass, not a SKREEM bypass. In other words, programmed keys would not be necessary, but his SKREEM still would be. The transponders are not the problem, the handshake between the ECM and SKREEM is the problem. A true bypass or immobilizer delete would involve rewriting the program for the ECM, as previously noted, so it no longer looks for authorization from the SKREEM. Not simple on this model. I see no need for a transponder bypass. Transponders are and always will be readily available. You will only be making your car easier to steal and you would still need a SKREEM module (his). But, to each his own. I'm going to keep my transponders and fix the SKREEM IF and WHEN necessary. So far, neither of our cars has ever had an issue. Of all the Crossfires we have worked on, only one or two had a real SKREEM hardware failure.
We look forward to seeing your finished product Viper-666.
The most part what you say is true and shows that you have a lot of expertise.
I would only disagree in a few points, i don't think that transponders from the 90s are always available. The ones used by mercedes were orginal from phillips and they weren't produced from them since a long time ago.
There are still replicas now, but you always have to see what quality you get. But the demand for these transponders is decreasing year by year because the number of cars using these transponders is decreasing. At some point the replicas are no longer worthwhile.
And as I know the transponders can not be copied so you can make max. 8 pieces for one skreem where mercedes has already preprogrammed the codes in the skreem. And new transponders can only be made with a lot of effort or if you be a dealer you can buy the codes from mercedes/chrysler.
My module would be, depending on the version, a bypass of the immobilizer, which then only needs the original key with transponder to extract new codes from the skreem. But in this version a working key would still be necessary to open and close the car and deactivate the alarm. In the bypass version the immobilizer would also be disabled because you can start the car with all keys who fit or simply by connecting the right wires how often shows in movies.
The Version 2 would also do the opening and closing and disarming of the alarm. And in addition, the transponder would have to be used before the start, so the immobilizer would be retained.
For all versions it would be possible to get a preprogrammed EEPROMs with 8000 codes and instructions how to program the PCM. When the codes are used up you can program the PCM again according to the instructions and use the codes again. This can be repeated infinitely. If you buy two EEPROMs preprogrammed by me you will always have 16.000 codes before you have to reprogram the PCM.
And to disable the immobilizer completely I agree that you have to find first a way to do this and then reprogram the PCM completely.