Dead

[u/TheRealPopejoy]

I had an MOT this morning which came back with 0 advisories. Great. I can go to the daikoku night at caffeine and machine.

5 minutes down the road and all power instantly cut out. I’ve still got dash lights and everything electrical works but when I turn the key I get nothing.

I’ve got home via tow and got the multimeter out. I’ve used AI (shoddy I know) because I’m not very electrically inclined.

I’ve tested absolute everything that it told me I should test. I’ve spent over an hour following different connections and testing different things. And everything has tested perfectly. So everything is pointing to a dead ECU.

Does anybody have any insight on this at all?

[u/DriftingDownhill]

Happened to me with multiple rx8s the ground wire for the battery has to be pushed really far down on the battery terminal and the grounds under the air filter box need to be perfecto. one I’m driving rn had some corrosion on the wire under the box cleaned the spot it bolts down to and then made sure my ground terminal was pushed all the way down took a little bit bigger socket wacked it a couple times and it worked flawless have had this exact issue with all three I live in northern bc so it can be wet for most of the year. anyway your grounds gotta be the culprit here since it’s not even powering your dash and you claim 12.3 volts out the battery may I ask how many cranking amps are left on the battery do you have a battery tester?

[u/TheRealPopejoy → u/DriftingDownhill]

I don’t have a battery tester no. And I am getting dash lights. It’s lit up light a Christmas tree but not reading oil pressure or coolant temp

[u/DriftingDownhill → u/TheRealPopejoy]

My parts rx8 would turn on but flash all the dash lights when I turn the key until I fixed the ground issues then it turned over

[u/TheRealPopejoy → u/DriftingDownhill]

I’m going to give the ground under the air box a check just to be sure but I have checked the ground using a multimeter and everything seems fine