Chrysler Repair: 1999 Chrysler 300M keyless entry, keyless entry system, diagnostic capability

Question
"Neither transmittors for my keyless entry will work. I have checked the batteries in both transmittors and they are new and it still doesn't work. This leads me to beleive that the module located inside the vehicle has gone bad. Where is that module located and what part may we need so that we can repair this ourselves by getting the needed part without having to take it to the dealership to be fixed? Thanks!";  

Answer
Hello gwe,
I have reviewed the keyless entry system for the 2001 300M in the Powertrain diagnostic manual, and if this is identical to the system in your 1999 then I would suggest that the problem may be a software and not a hardware problem. The sentry key immobilizer module is part of the body computer and the system is a digitally operated device that has a lot of built in diagnostic capability. I believe that without the diagnostic readout box (DRB III, costs about $6,000) and the manual/training in the system you will not be able to service this problem on your own. I would instead spend your energy and money on identifying a dealer with the person who is well versed in the system, who has the equipment and experience to correct the problem quickly at the least expenditure of time and materials. It is not something that can be accomplished by the amateur mechanic, and I do not reach that conclusion easily. There may be no new hardware that you need but that is not certain. But the only efficient way to get back the keyless entry function is to have the dealer do it.
Roland