I would start (pun intended) with a very close inspection of the RCM module relays and solder joints. The reason I would try this FREE inspection is you indicated the car does something akin to turning on but the starter doesn't engage. When you push the start button, does anything else happen like gauges work, cluster lights light up (self check) and such? Any 'whirring' sound (fuel pump starts and pressurizes system), these things help troubleshoot. Most of what your saying involves replacing the existing system and has nothing to do with figuring out what is and what isn't working when you try to start the car. Not knowing how the system is installed and how it is supposed to work, makes it almost impossible to troubleshoot let along doing it over a chat forum. One more thing, if the remote start system has more than one fuse (or one fuse) have you checked to see if it (they) are all good? Also, have you at least checked all the fuses in the under hood fuse boxes associated with starting the car (and sometimes people find a fuse that is providing a 'hot' for the remote start system that isn't involved in the starting/running systems). This whole thing can be a simple hidden fuse that went south. This problem is going to be extremely hard to troubleshoot if you haven't checked all the car fuses and any fuse that is involved with this added remote start system. I (and I am sure many other members) do not envy your situation here, it may be quite a while before it is found and fixed (if ever).






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