mx5cartalk.com

sorry for starting a new thread, but I'm having issues similar to that explained by psi-mx5 in another thread.

basically was at the WA mx5 sprint event last night, and on a couple of runs noticed that my radio & dash lights would flicker on corners (not sure if it happens on both left & right turns coz wasn't really paying attention)

however on one of my last runs of the night, it flickered and i briefly lost power to the car causing the back to step out and i spun the car. first couple of times i turned the key..nothing..then finally after about 6 tries ..it started back up and i was able to complete another few laps without issues

any ideas what could cause this?

Battery connections?

first thing i check this morning. connections are tight. followed the ground connection to the body looks ok.

might just take it to a workshop and get it scanned for error codes.

Yeah i'd have guessed the battery connections and made sure nothing was touching the terminals.

If you'd have said something last night I had an OBDII reader with me, we could have looked for error codes.

Could also be worth checking for a loose fuse.

Assuming the battery connection is ok, check the connections to the main fuse (80 amps) in the engine bay.

If that checks out ok, could it be ignition barrel related?

I just took a look a the wiring diagram (get them at http://www.madracki.com/miata/wiring.html). Basically, the positive supply circuit from the battery runs something like:

Battery
Main fuse (probably 80 amps)
Ignition switch
Main relay
Everything else

So, to lose power to everything, I'd say one of those items has to be faulty. I know you checked the battery connections, but have you physically taken them off and cleaned them? I'd also check the voltage coming off the battery.

Following that, I'd check the connections to the main fuse and main relay are all ok, then the connections to the ignition barrel.

I guess the other possibility is something shorting to ground, but not for sufficient time to blow the fuse.

May sound stupid, but by the ignition barrell are u referring to thr key ignition?

Yep.

i dont think it would be the ignition barrel, if your turn the key off the lights still stay on with the mx5's. i would say its alternator / battery related. Check your alternator charge and check your relay box for any fuses that are no good, or not inserted correctly.

That's quite a good point, did the headlights stay on after te power cut out on Sunday night?

yea lights on dash stayed on....just nothing when turning the key..not even a weak crank. foot definately on the clutch ...so wasn't that switch either. after a couple of tries, it started back up without any hesitation.