Parasitic Load?

[Benckj]

Never measured the load on my other MR2 so can't compare. Brought the Exide battery in to local shop and he checked with condition meter. Result came up with 'Bad battery-Replace' so he handed me a new one and off I went. Took all of 30 secs so too easy.

[mknz]

The old alternator likely placed extra strain on the battery damaging it. I've seen it happen many times before; customers want a replacement under warranty, their alternator is faulty, Century won't cover it because of that. They get a new battery and alternator and their battery lasts for many years afterwards. I've only seen a Century battery fail due to a manufacturing fault once a year out of hundreds sold.

Same story with Bosch battery warranty

[Benckj]

Had my alternator checked on bench and it generated 83amps @14.6vdc. Should have replaced with new 120amp model but will do shortly.

No doubt the constant load on battery without regular recharge killed it. This is why I went with a top notch highly rated 4wd battery. Very pleased Exide replaced and have created a long term customer in the process.

[mknz]

Had my alternator checked on bench and it generated 83amps @14.6vdc

That seems normal, if the voltage wasn't fluctuating then it's the battery. The high parasitic load you can't do much about, unfortunately.

[vrtigo]

My 5A drain was caused by a short in the alternator. Check for continuity between the B+ terminal and ground - there should be none.

[GDII]

I'd be interested to know what yours is Phil. I didn't find the 85ma exceptional which is why I'm surprised my battery is falling short every week. Granted this was only a spot check and could vary up and down based on battery voltage levels and ambient temperatures. I might just check my 96NA so I have something else to compare it with although there are many differences between the two vehicles including the remote key entry on my turbo which is stock.

I will leave in car until weekend and if its dead again it will be time to pull out and bring in for testing at Exide depot. Not much sense in re-conditioning if I can get a replacement under warranty. Looking at buying a new 130amp alternator Stateside to replace my stock 90amp one. Will cost approx. $260NZD delivered. Not a solution to the problem but its something I should have done when I dropped engine 2 years ago. Hope to do a decent road trip later this year.

I have finally been able to test my load. This is with the radio unplugged though.
I found with all the fuses in I get 0.27mA. With the DOME fuse unplugged I get 0.25mA. However for some reason the battery went flat over a week but in saying that I don't believe after it went flat due to a user error on my part that I had fully charged it. It's a tiny load so will keep an eye on it. I havne't found where the 0.25mA load is as I have not done testing on the fuse box in the driver side foot well.
I never had issues like this before as I drove the car everyday and now not so much.

[Benckj]

Good to hear a report back on outcome. Looking back with mine it was due to alternator diodes and my AGM battery. Even after replacing alternator and battery it still didn’t stay charged. The AGM selected requires a decent charge which only occurred after taking car for drive to Manfield. Using a battery charger or short runs just didn’t do it.