Morning everyone from Hawaii,

So I just picked up an 04 Cooper S from an abandoned car auction that has been sitting for god knows how long. I’ve been working on it over the past week to try to get it back up and running. New battery, new plugs, fresh gas and fuel filter, new oil all the basic maintenance things. The car came without a key so I had a locksmith made me one. The key will allow the cars electronics to function and even allow the car to crank but it won’t fire up. I’ve checked all fuses and relays and everything seems to be fine. Now I’m leaning towards a possible EWS/ CAS issue. Is there a way to diagnose if one or both are bad? Any help would be appreciated, I’m new to Mini’s so I’m lost at the moment!

edit: the locksmith gave me a 3 button key but as I’m doing more research it looks like 04’s came with a 2 button key fob. Can anyone confirm this? And is a 3 button key not compatible?

 

There's no CAS in these cars, just the EWS. CAS was a system introduced later by BMW that consolidated the door locks / key fob electronics with the EWS.
The EWS will not allow the starter motor to operate if the key isn't recognized - so this probably isn't your issue.
Do yourself a favor and get a BMW/Mini specific scan tool which will allow you to scan error codes throughout the vehicle - including the EWS module. There might be some codes that will point you towards your issue. Also, start with the basics- check compression, spark, fuel, etc.

Yes, 3 button fobs came out for MY 2005. I might be mistaken, but I think they're compatible with 2 button fobs (at least they should be since the vehicle's electronics are the same). If your fob can unlock doors and open windows then you've confirmed this.

 

Thank you so much for the info! It was super helpful. I think i have found my issue, I replaced the fuel filter but I don’t think it was put back together correctly because there was no fuel pressure. I broke the o-ring so I’m waiting on parts now before I can re-test but I’m hopeful that’s my issue. Is there a specific scan tool you recommend for BMW/Mini? I have a basic Foxwell one now that works great on my truck and wife’s Jetta but it won’t read any engine codes so looks like I’ll be looking for a new one.