Do I need a new alternator?

SDG

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2002 Mazda Protege5
My battery light came on last night. It was going on and off...so I kept driving and then I blew out my passenger headlight(that makes about 6 blown headlights since owning this car). I have had previous power issues with my Protege5 and have replaced the belts a couple times which did the trick. I replaced them before because they ripped off while I was driving. Now the belts look ok and are spinning so I suspect the alternator is shot if the battery isn't charging.

I was driving tonight and the battery light came back on and the lights died a few minutes later. Then it wouldn't start, so I bought a new battery so I could at least get home. The new battery started the car but the light came back on. Do I need an alternator?

Is there a way autozone can check if I need a new one or if its belts?

What does a rebuilt alternator run? I suppose I can get the part and have a mobile mechanic do the work. I don't know any Mazda mechanics here in Vegas so if anyone knows someone let me know!

Any advice? Ugh..I already spent 100 bucks on a battery...bummer.
 
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Hmm..I'm thinking maybe I should just change it out myself. How hard is it to remove through the top? Remove the strut brace, power steering and I should be able to get to it yes? That would save me the money of whatever a mechanic would charge me.
 
start the car and pull the negative terminal off... if the car dies its the altenator

if you going to try and change it yourself... pull it out throught the top... its way easier to move the cruise control and strut bar then it is trying to manuver it throught the bottom

i bought an alternator from napa for $118 after returning the core
 
Isn't it possible to kill an alternator by checking it via that method? I thought I read that on another thread.

Its a brand new battery so I think it will make it to the autozone for them to check it. I made it home from where it broke down on the charge it had...about a 15 minute ride..so actually it might not have that much juice left.
 
well if your battery is fully charged it should make the 15minute trip. About frying the alternator. I've never heard that cuz basically when u start the car it's running off the alternator. The battery just there to start the car
 
i don't really see how you could kill it doing that. the only way would be if you disconnected the positive and put it back on when the car was still running and the key was still turned.
 
you may fry the ecu if you take off the battery cable with the car running. best to take it to some place that can run a test on it.
 
So after I got my car started it was just running off the juice from the new battery correct? The battery light came right back on and stayed on the whole drive home. How much juice does a new battery have? I don't want to get stuck on the way to the autozone to have it tested. I would have to recharge the battery to get it running again.
 
if the battery is running down while you are driving, the alternator is dead for sure. you have to remove the alternator to get it tested, but odds are that you will need to get a new alternator anyways.
 
Well I don't know if its running down or not now since I put a brand new battery in it...but the battery light is on so I assume its not charging and just running off the new battery juice. The battery I had in it before ran down and died so the alternator or battery was shot..one or the other. I am assuming the battery light staying on is because the alternator is not charging. Am I making sense? If your alternator is dead and you put a brand new battery in the car will it drive?

As a side note..the old battery had a lot of corrosion around the posts..don't know if that means anything special or not.
 
a new or newly charged battery will run the car until the battery dies. it's just like a battery operated car at that point, since it won't charge anymore.
 
It's your alternator...trust me!!! I had the same problem and I just changed my alternator and problem solved.
 
Yeah, I'm sure you are right. I should probably just order one from autozone and try and do the work myself. I'm not all that mechanically inclined but after reading about how to do it through the top I think I can figure it out.

What does an alternator cost, 170 bucks?

I don't want to take it to a dealership...can't afford that...better off trying to do it myself and as a last resort hiring a mobile mechanic.
 
all that i am finding is $170 if you have a rebuildable core to return. that is another reason why you should go ahead and pull it before you try to get it tested. you may find it cheaper at oreilley's or advance, so you could try there also.
 
FYI, the new alternator I got had a red warning sticker on it saying something about NOT testing the alternator while it was off the car. I'm saying this in respect to taking it off & having it tested not pulling cable off while running to see if car dies. That is test enough. So is the battery draining with the light on on the dash. Change it thru the top removing strut bar & cruise control as was stated.................http://www.floptical.net/mazda/
 
Yeah I was able to make it to work this morning on battery power. I am going to try and make it to the autozone on the way home and have them test it while its still on the car just to be sure it isn't belts. I am 99.999% sure its the alternator but since I have had multiple problems with belts I want to be sure before spending another 200 bucks.

I plan to fix it on my day off on new years day. Sounds like a major PITA but hopefully I can figure it out. I have changed the belts a couple times so it seems similar. Do I need to remove the passenger side wheel and jack the car up like you do with the belts?
 
by the way..what tools do I need to switch out the alternator? I want to make sure I have all I need before attempting the task.
 
Wheel off to change belts????? Uneccessary. Jacking up car for access to bottom of alt is neccessary. Disconnect battery. Remove the stb. Unbolt cc & move it out of the way. Get under car to loosen the mounting bolt on alternator. Loosen adj & belt. Remove the top adj bracket from the motor-1 bolt. Remove the canister on the firewall, move it out of the way. Pry alternator from it's mounting point. Wiggle it it thru close to where the canister & cc was mounted. Twist it around to find best exit route. Put new one back in reverse. Only takes normal hand tools. 10,12 & 14mm wrench,sockets & something to pry it loose from mounting on bottom.
 

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