Hello from Miami, Florida,

So I come here to the forum with a little bit of an issue that I need some help with but before I get down to the problem let me let you gentlemen know a little bit about little caprice (My R53's name) LOL. Anyway, she's a 2005 JCW with stock air box **flap removed**, MSD COIL, MSD wires, Brisk Racing Plugs 2 Steps Colder than factory, Resonator delete, and that's pretty much it. Moving forward I recently changed the factory radio for an aftermarket radio and did the install myself bypassing the Harmon Kardon amp and the sound system sounded great. However, three days of daily driving my check engine light comes on at a redlight and since I was on the way home maybe like 15-20 minutes away I said hmmm checked all my gauges and every thing seemed like maybe a false CEL. But as I got closer to my house my batter indicator light came one and so did the ABS and the steering got hard. Since it was nighttime and it was clear that their was something wrong I quickly turned the radio off, turned off the A/C,and lights to try to conserve enough battery since im only like 3 blocks away and I can do it safely with hazards on. So I get home and I checked the tension on my belt and it was fine, then I proceed to test the battery which was weak, and it ended up being my alternator so I bought a remanufactured one from the local parts shop here and installed it myself. Everything was fixed the battery was recharged so I put it all back together and their I was back to normal again, well at least thats what I thought. Until the other day I was doing some 2nd and 3rd gear pulls for fun and noticed something real strange. As I climbed the RPM's to 5,500 RPM to 6,500 rpm I noticed the car's interior illumination looses power for a split second and comes back on while the gauges go crazy and reset themselves. It does it only while im driving under FOT and High RPM... Something else I almost forgot to mention is while doing this spirited driving I did have the car in the hidden menu under test 9 to see what my current voltage is and to make sure my car was charging properly and it is @ 13.8- 14.00 volts. However, I have no idea why the car is doing this crazy loss of illumination in the gauges and reset in the middle of a hard pull. It scares the lights out of me and I want to avoid any damage so Im driving the car really conservatively until I can find the root of the problem.This is really weird and I hope someone can offer some help since Im new to the Mini world. Do I have an ECU problem? Can a faulty radio wire cause this issue?

 

Check all your major grounds for corrosion and continuity.