alternator problems

[Rex7]

what gives i've gone through 3 of alternators in a years time. would an aftermarket pulley cause the problem. i've also relocated the battery to rear of the car.

[Phoenix7]

well, I'm having the same problem with my S5. I've been through 3 in the past 6 months.

I Keep killing the voltage regulator. I was told that it could be a faulty battery or the wiring that goes from the B-terminal to the battery. I just rewired the connection from the B-terminal to the battery (bypassing the stock one) and I'm going to see if the Alternator dies again.

IF the alternator survives longer than 2 months (that's the time it took to kill the last alternator) then I know it's the wiring. If not then I'll try another battery.

I feel your pain.

Now, IF your belts are not tensioned properly they could cause your alternator to fail. You can't have one tight and another one loose. You can't have them both on too tight and you can't have both too loose. Screwed if you do and screwed if you dont.

Double check to make sure the alternator, pullies and belts are in good shape and try avoid the issues above.

[Rex7]

i've only got one belt. I did the rewire to the terminal. i'm waiting on a battery to come in tomarrow. i've got a yellow top it's only 625 ca and i'm getting a red top with 910 ca.

[Phoenix7]

cool. Did you do the re-wire on the current, dead, alternator? or on the new, WORKING, alternator you're getting?

[Rex7]

the current or dead one had the rewire.

[Phoenix7]

hmmm, how long did it last with the wire? Did it last longer than the old alternator?

Let's hope it's a bad battery (it happens sometimes) otherwise we'd need to figure out what the problem is (since I JUST did the rewire on the alternator with the new voltage regulator and I'm not sure if the problem will persist.) if the modification + new battery doesn't help.

Let me know how it goes for you.

[85rx-7gsl-se]

What kinda Voltage is it putting out when it works?

[Rex7]

the last alternator lasted about a month and a half. but when i got it the casing on it was cracked. got it from auto zone. they're replacing it for me. i'm hoping it's the battery. it's been over charged by a battery charger that got posessed. been left completely dead for 5 mos. when i was in alaska. it even had juice come out of it once. it has been around for the last 4 years and always tested fine at auto zone. as far as voltage it usualy reads 14.1 to 14.6.

[Phoenix7]

well, we both agree that it takes 1.5 to 2 months for the alternator to die so let's see how it goes. You may have battery issues and I may have wiring issues. How crappy.

I've never had problems with my yellow top so i think the red top should be fine but they may require special procedures to recharge. I accidentally killed the yellow top in my TII when I charged it improperly. Keep that in mind.

[Rex7]

Phoenix7 with my battery issues your wiring issues we might be able to get one of them right.lol. got done putting everything in today voltage is back to reading 14.4. hopefuly everything goes well.

[Phoenix7]

:lol: Let's hope it doesn't act up. We'll know in a month or two.

[Oliv]

My voltage can vary from 13.7 at iddle to 14.4. something wrong here?

[DaveW]

Somewhat off subject, but rebuilt alternators often can be junk. Just because it was old, I replaced a perfectly good but 190K mile alternator on a Chevy Van I use to tow my racecar with a rebuilt - the rebuilt died (bearing failure) in less than 10K miles, and I had to reinstall the 190K one in the middle of the night on the road.

Rebuilders often just replace enough stuff so it works, everything else not absolutely needed is still the original old stuff.

[DaveW]

My voltage can vary from 13.7 at iddle to 14.4. something wrong here?

sounds normal to me...

[blwnrtr93]

^ That's what I was thinking. The voltage isn't going to be 100% constant, but will usually vary from 13.5 - 16.5 volts depending on the system. My old truck (63 Chevy V-8 conv. w/ stock I-6 alt.) used to see 14.4 constant (didn't have a radio or any accessories).

[Phoenix7]

well, mine's back down to 12. It's not the Bterminal wires. I have to replace the battery terminals and put my TII's battery in it and see if that fixes it.

[Rex7]

i made it a month with no probs as far as charging goes. now im having the no start problem

[Phoenix7]

Battery cables?

[ryan1]

I was having charging and slow crank when hot problems. After trying many things, I replaced the 120 amp main fuse, and that fixed all my problems. The fuse wasn't blown, ohmed good, and didn't drop voltage across it. I don't understand what was wrong with it, but it instantly cured the slow crank and low system voltage problems.

[Phoenix7]

HMMMM! I'll look into it, thanks for the tip.

[Rex7]

Battery cables?

don't think it's the cables. i'll double check. doesn't even do the click.

[Rex7]

found the culprit. heard a noise coming from the driver side kick panel. the relay for the security system was not working. I took out the relay and put a jumper wire on the plug. it now works.

[speedjunkie]

I got an upgraded (140a) alternator from IR Performance a couple months ago. It's been working great but now I'm having charging issues. I'm not sure that it's the alt because I haven't checked it at the terminals yet, but I'm only getting between 10 and 12v at idle now according to my turbo timer. It goes up to 13 to 14v at a few thousand RPMs but IIRC I had that at idle before.

I installed my stereo (didn't have one for a while) and new door speakers this weekend and when I went to start the car it was really low. I jumped it and let it run for a while. Tried to start it again a few minutes later and had to jump it again. I disconnected the stereo to see if maybe it was grounding itself out or something and see what would happen. It starts on it's own now, but just barely, and like I said, it's only getting 10 - 12v at idle.

I really hope it's only the main fuse or the security relay or something. I never really thought about it before but should I change the main fuse to a higher rating since the alt puts out 140a? I'm not good with wiring and stuff like this.

[rx4ur7]

DO NOT PUT A LARGER FUSE IN! You will just overload the wiring. Check for bad grounds, voltage drop in any wiring, clean battery term ends.
I would caution everyone on jump starting any vehicle built after 1990. Or any car that is reliant on electronic controls.
Incorrect jump starting has been the cause of many ecu failures to either vehicle due to high voltage or amp surging, especially if the jumped car has a dead battery.
Safest of course is to remove battery and charge it.
If the battery is just low, the safest is to hook up the cables and have the jumper run for a while. Shut the jumper car off then start the jumped car.
It only takes a milliamp to blow circuits in ecu's.
Jump starting is the main cause of ignitor failure in the first gen 7's. I have a box full of dead ignitors that are proof.
I will continue with my mantra, check all grounds, check for high resistance and voltage drop. Get a book on basic electrical testing procedures.
Get a Mazda altenator, I have never had any luck with rebuilds. In all the Mazda altenators and starters I have replaced in 30+year I have had two, one of each that were bad and they failed in the first week of use.
Yes aftermarkets have great warrenties, if you like replacing them every 6 months.
Personally I do not want to see a vehicle again for the same issue.
Usually the only times I see odd ball failures is from someone thinking they can out engineer the factory or have rewired the car and missed something.
The other times, bad grounds.
If you have a good battery 12.5 to 14.7 at idle with no load is normal. (12.5 for fully charged)
Mazda specs
B term key on Va (battery) 14.1-14.7 idle
L term ~1 12.9- 13.5
S term Va 14.1 - 14.7
One other thing-
Check for draw, easiet way, disconnect ground cable and put a test light, not a DVM, between cable and battery, if it lights you have a draw.
Pull fuses until you find the circuit. I it still stays on disconnect alt. On a vehicle that has not been tampered with you should find the problem. If not, you are in for a long slog of aggrevation, good luck.
On new cars there is always some sort of draw, but it should not be enough to power a light bulb.
Hope this is of some help.

[speedjunkie]

Okie-dokie, thanks!

I have some work to do tonight :)

[speedjunkie]

OK so I discovered a few things tonight.

I tested the alternator, and realized that it's putting out what it's supposed to if I don't have my A/C on. I turn the A/C on in order to turn the fans on. When I have the fans on, the alt is only putting out around 11 or 12v. With the fans off it's putting out around 13 to 14.3v. Both of those measurements are at idle.

I checked all the leads on the alt and discovered something very strange...all my checks were at idle btw. On B I got 14.3 IIRC. On S and L I got zero, zilch, nada. Which is weird because supposedly it's still charging the battery, if only a little. So I checked my roommate's FD. He has a stock alt. On B and S he got 14.7, on L he got 0.1. Also weird.

I did a check for draw, and the tester did light up. So I started removing fuses. I was in the relay/fuse box under the hood, and when I took out the BTN fuse, the light went off. Bingo. After looking in my FSM and not really finding anything but wiring diagrams (which are helpful but I'm looking for something simpler at this point haha), I'm doing a search here. My manual is so jacked up for some reason. Sections aren't where they're supposed to be, they're not WHAT they're supposed to be, you name it.

EDIT: OK, after checking the electrical repair manual, I discovered that BTN was for ALL FUSES...which doesn't help me a damn bit, other than to tell me the problem is somewhere in the fuses...which I already knew. HAHA.

[speedjunkie]

Alright, I narrowed the problem down to automatic door locks and my aftermarket gauges drawing on the system. The 10a fuse for "room" was the one that killed the light. So I started unplugging things in the interior, and when I got to the doors it killed the light (after putting the 10a back in of course). Then I was putting the other fuses back in and noticed there was still an issue and traced it to the gauges. I unplugged the gauges and it killed the light.

I'm not sure how new this problem is, but my problems with this battery have been pretty seldom. I'm also not sure how much it's actually drawing on the battery.