First off I want to say that I have been trying to search(with google using site:rx8club.com in my search) for my specific problem for the last 2 hours and can't seem to find anything just like it. Trust me, I've really been trying.

Vehicle Specifics
USDM 2005 RX8 6spd MT
Mods include BHR Ignition kit. That's it.
Oh, and BRAND new DieHard Gold battery(680 CCA)

The problem in short:
Turn key to ON = all electricals work(dash on, radio on etc).
Try to start engine = ONE click, no crank, no dash ,no electricals for 5-10ish minutes
Clock reset, radio stations reset, DSC needs to be recalibrated(the turn wheel to lock one side then lock on other thingy).


The long story:
I walked out to the 8 and tried to unlock it with key FOB(switchblade key). The lights didn't flash and doors didn't unlock. Tried a couple times = nothing. Key is working fine. There is power and battery was changed about 2 months ago. Used the key itself to unlock doors. Open the door, sat down, alarm sounded. Disengaged alarm with the FOB.

Turned the key to the ON position. Everything SEEMED normal, except clock was reset and "DSC OFF" light was flashing. Turned steering wheel to one side lock, then other side lock = DSC recalibrated. Turned key to start the engine and BAM.....nothing. Literally. No crank. No electricity. Nothing. All there was was ONE "click", and everything went dark . Couldn't try again for about 10 minutes because no electricity. Almost like the battery wasn't connected(yes I checked, it was connected). Tried again. Clock reset, DSC OFF flashing. Start car = no crank, the dashboard goes black, LED display off. Nothing works.

This has happened a couple times before I replaced coils, plugs, wires and battery, and it would always work the second try. But this last time, it wouldn't give. I checked the grounds, the fuses, battery terminals. Everything is clean and/or in good condition.

In dire need of some help!!!!! I will probably be taking the 8 to the dealership if I can't get this resolved soon.

 

You sure the battery isn't dead?

 

You may have a parasitic current somewhere while the car is off, which drained the battery. Weird that you were able to get it started on a secobd attempt before. That sounds more like a starter relay problem, but there is not enough info to conclude anything.

Do you have a multimeter? Measure the battery voltage, thrn disconnect the negative cable, make sure all lights and accessories are off and doors are closed and measure the current between your disconnected negative battery terminal and the negative battery post. Measure for 5-10 seconds, until the reading stabilizes. Report back.

Be careful not to use your hand to complete the circuit between battery and thr car's wiring

 

If you just put battery in make sure connection is tight

 

Yes it is tight. And the connectors are clean too, since I just cleaned them when I put the new battery in last weekend.

I tried looking at the starter and from what I could see without lifting the car, the terminals and wiring looked okay. I was planning on replacing/upgrading the starter any way since it sounds like it still has the old 11 tooth starter(when it actually wanted to start ).

 

Just checked. Battery alone = 12.8v. Negative battery to negative cable = 12.0v.

 

Sorry, I should have been clearer. Voltage at the post, current (amperage) between the post and the loose negative cable. The current should be about 0.01amp or 10 milliamps. Maybe 20mA. But not over 50mA.

12.8 is a full battery though. So it's not that. Something is causing your battery to not be a ble to deliver current to the rest of the car, and the thing all the affected systems have in common are the battery clamps/cables.

Can you take a photo of them? Is there any grease, dirt, powder or corrosion on them? Are they snug that you can't turn the clamp on the post?

 

The clamps/connectors are snug tight, can't move. The negative clamp does have a little bit of dirt but I've wiped most of it off from the contact points.

 

Did you check the main 120 amp fuse?

 

Yep, that's fine. Same with all the other fuses.

 

Thanks I found this.... Im having the same problem and I would like to know if you found the solution to your problem... thanks

 

Not yet. If I remember correctly, the old starters on '04-'05(apart from being weak, slow starters) may cause weird electrical anamolies, but I could be wrong. So I ordered an upgraded starter in hopes that may be it. Won't get it until around Friday, but I'll keep everyone posted.

 

The next thing all the affected circuits have in common is the battery ground strap. Check where it connects to the chassis, maybe the connection needs to be cleaned/derusted.

 

So I replaced the starter. It started up just fine. Drove it around the block, then shut it off while I dropped off my tools at the apartment. Go back out minutes later to see if it will start. Same exact thing happened again.

 

Its dead again? Check the voltage at the starter. Can you try to figure out what was wrong with the old starter (or the new one but the older one's probably easier)

Edit: Woops i think you already checked the voltage. Anything you might have done wrong during the replacement causing the starter to go bust?

 

I think if a new starter didn't fix it, there is nothing wrong with the starter. Electrical gremlins suck, but you can beat them if you're methodical.

If I understand this well, you lose all current when it doesn't start, since the clock gets reset. So something is breaking the circuit between the battery and the rest of the car. The clock circuit is always on, so for that and the radio and the starter to all go down, you need a fault that's common to all those circuits. The battery is one, but we have eliminated that. Next would be the ground strap from the neg post to the chassis. After that, I think you're looking at the main fuse or other big connections on the positive strap.

Work backwards from the battery and check/eliminate every connection. You should find something. It's not uncommon for the grounding points to rust and fail to ground properly. The intermittent nature of the problem suggests that a connection is loose.

 

Turns out it was the POSITIVE terminal wire gone bust. I eventually was like "f*** it, taking it to the dealership", and they figured out. The entire time I was looking at negative/ground.