I replaced my stock battery with a miata battery when I installed my greddy FMIC. It worked fine for the first couple of months but now it doesn't have enough juice to start the car after sitting for 2 days. Has anybody else had this problem? I'm wondering if it's the battery or if there is a power drain somewhere.

-Chris C.

 

Hmm.. I have no experience with the Miata battery. I have a PC680 Hawker Odyssey and it works great for me, I have let my car sit for a 3-4weeks once and it started right up. I know of others who have had the same problem you do. Assuming your alternator is up to the task, I would guess that something is draining the battery.. it should hold a charge for a lot longer than that.

Matt

 

Do you have the fan switch mod?

 

i was wondering the same thing...i used a miata battery in my previous fd with aftermarket alarm and it started up fine after a week. don't see how an intercooler would have anything to do with it, but that was with an m2 medium. now with my present fd with a greddy 3-row and no aftermarket alarm (i also don't arm the factory alarm), i can't start the car up after 3 days.
i think there's a power drain somewhere...just been to lazy to check.

 

Nope never had a problem. Must be YOU!!

 

I too have the power drain after three days and I am on the stock ic...it could be some other electrical device that was installed...ie. Turbotimer, gauges with backlights, aftermarket alarm, and anything else electrical that you installed...Anyway, I also have been too lazy to search for the problem....I guess when jumping the car every weekend drives me nutz then I will seek it out

 

Maybe you could check the parisitic draw on the battery when the car is off with a ammeter, that way you could see if something is draining the batt

 

FWIW, If you have the fan mod and leave the switch on you will run down the battery.

 

I had the battery relocating kit from M2 and the Odessy battery did not work after 4 months. I had No problems with the charging system. I think I just got a defective battery. I replaced it with the Miata battery and NO problems here. You must have a problem in your charging system.

 

Haha, Mike you've had the miata battery for less than a week, I think it's too early for you to say "never."

Regardless of how long "never" should be I guess I'm not the only one with this problem. I don't have an aftermarket alarm. I do have a blitz duel turbo timer with the factory harness adaptor. I have had that for years and haven't had a problem. Marshall I don’t have a fan mod switch , but I lowered the threshold for when they come on using the PFC (88c while driving). The fans generally do not run when I shut the car off.


I guess I'll take a closer look at everything before ordering a new battery. I removed one of the horns when I installed the FMIC. To the best of my recollection I simply wrapped the connector with electrical tape and left it dangling. Should the connector be grounded?

I'll look into getting an amp meter. I know nothing about that stuff though aside from a vague recollection of high school physics. I guess I'll have to learn out of necessity :p If I find there is a draw from the battery how do you then locate the source with a meter?

 

Hey guys, I think I may have found the cause of my problem. This morning I sanded my battery terminals in hopes of getting a better connection. While I was doing it I noticed a wire that was the similar in color the the other stock wires, but much smaller. I traced it back to the firewall. Inside the car it turned and went behind the dead pedal. I removed the pedal and a spagetti dish worth of wires fell out and behind them was a glowing red light! Apparently the original owner had an aftermarket alarm installed. The "Brain" was gone but all the actuators and sensors were still there (that's been said about me too). I still can't believe how much stuff was hidden back there. The install quality was terrible. The factory wires were cut and twisted together with the alarm compenents.

I spent several hours removing everything and then took the car to a stereo shop and had them solder and reseal the factory wires. Hopefully that is the source of my battery problem. I guess I will know tomorrow morning.

 

Here is a picture of everything I removed

 

Just curious, did you see any named stuff so you know if he installed a decent alarm or not?

 

"Audiovox" is the brand name. The parts are made in mexico. Crappy alarm case closed. Sounds in Motion carries Audiovox. The original owner spent a couple thousand on an aftermarket stereo with them. The quality of the alarm and stereo install is the same (terrible). They probably recomended the alarm and he didn't question it. Poor car has had to suffer all these years without anybody knowing.

 

The charging system in the RX cannot adequately charge the gell cell Miata battery. I was told this by an alternator/starter rebuild shop. I had the same problem. I went with the Optima yellow top and it works awesome. $160 buck though. It also fits perfectly in the rear bin. I moved the whole stock battery mount to the bin. You must cut the bottom of the bin out.

 

The way to test for parasitic drain it to hook up am ammeter in series with the circuit, and if there is a significnt amount of drain ( I'm not sure what that # would be, maybe over 10ma ?), them start pulling fuses. Although, in your case this may not have worked cause it may not have been on the factory fused circuits.