Bought my R3 a month ago and I could never get the courtesy lights to come on. I had some really annoying dealer bullshit that one of the previous dealers did to save money on...

Group 26 battery with loose posts, no J bolts to hold it down, and no battery cover. It kept resetting the PCM and all CAN modules when I cranked the car. The battery was f'ed so I replaced it with a 35AGM, bought the J bolts and the cover and clamped everything down. Immediate +4 mpg.


This weekend I was installing a amp and some lights and I added another 4 gauge cable from the battery to the body and didn't think to much of it. This morning I opened my driver door and got hit with a ridiculous light from the passenger courtesy light. I was like WHOA, never seen that before....

The car seemed to be doing ok after that 35 battery, before I even added the extra 4 gauge. Do the series 2 have grounding issues after only a few years of use? It was just really weird that they both seemed burnt out.

The ground from the passenger side engine to the body looked like it was 8 gauge or less, but I thought that was just Mazda being cheap. I know the Renesis has a pissy ignition system and hates having subpar grounds. I figured that out when I was getting 9mpg.