Ok I bought a 2003 P5 for $200.00. It came from a family member. They installed a new battery because the car had sat for about 5 months and the thing was dead. I drove it home from their house and noticed that the battery light was on no big deal maybe it stays on because it is faulty. Well I went out the next day to drive it to work and started it up to warm it up. I let it run about 10 minutes then went out to get in it and as soon as I sat down it stalled then wouldn't turn over. I jumped it drove it to work got to work shut it off dead wouldn't re start. I let it sit all day went out it was god to go started right up. Came home took the alternator off took it to autozone had it tested. It tested ok but I replaced it anyways because it was the orignal one with 90k on it. So I installed the remaned and started it up boom the light stays off so I take it for a spin as soon as I get about 2k rpm the light comes on. drop it out of 4th gear into nuetral and the light goes out. SO I get it back home. Take the battery out take it to have it tested for a dead cell. Autozone tested it at 89% charge so it was good at 12.4 volts. The guy tells me to bring the car up after I get the battery back in. They test it and it pegs the volt meter. 16. something volts. So now it is over charging and I am pulling my hair out. Please help any help would be awesome.
Electrical Nitemare.
- Thread starter Daniel315
- Start date
WAIT! at 16.0 Volts, the alternator is "full fielding" it will likely be fluctuating from 12.5v and back up to 16.0v .
Also, anytime the red battery light on the dash is illuminated, the battery is not being charged. That DOES NOT mean necessarily that the alternator is faulty.
Could be the Battery. Could be alternator. Could be wiring in between Alternator & battery. Could be the Fuse. Could be Bad ground from Alternator. Could be a faulty PCM(not uncommon in this case) It could very well be a faulty aftermarket Alt. But the OEM tested good right? Look elsewhere before condemning it again and be sure its the Alternator...really.
That being said, The voltage does not charge batteries, Amp's does. 12.5 volts with 80 amps is still a good Alt.
Know this: On these cars the Voltage is regulated by the PCM.
Mazda don't do well with Gypsie built Alternators. Get an OEM Alt if you find it to be faulty.
I know I'm giving you allot of info , but I've seen this a hundred times times on lots of makes and models. If all the wiring, fuses, battery, PCM check out good...get an QUALITY OEM Alternator AND SKIP THE AFTERMARKET CRAP. THIS IS ONE OF THOSE TIMES YOU NEED TO GO WITH OEM.
Let us know what happens. Good Luck.
Also, anytime the red battery light on the dash is illuminated, the battery is not being charged. That DOES NOT mean necessarily that the alternator is faulty.
Could be the Battery. Could be alternator. Could be wiring in between Alternator & battery. Could be the Fuse. Could be Bad ground from Alternator. Could be a faulty PCM(not uncommon in this case) It could very well be a faulty aftermarket Alt. But the OEM tested good right? Look elsewhere before condemning it again and be sure its the Alternator...really.
That being said, The voltage does not charge batteries, Amp's does. 12.5 volts with 80 amps is still a good Alt.
Know this: On these cars the Voltage is regulated by the PCM.
Mazda don't do well with Gypsie built Alternators. Get an OEM Alt if you find it to be faulty.
I know I'm giving you allot of info , but I've seen this a hundred times times on lots of makes and models. If all the wiring, fuses, battery, PCM check out good...get an QUALITY OEM Alternator AND SKIP THE AFTERMARKET CRAP. THIS IS ONE OF THOSE TIMES YOU NEED TO GO WITH OEM.
Let us know what happens. Good Luck.
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whatusername
Member
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- 02 protege5
pish tosh on that i work for autozone and never heard of having 5 bad alt 1 after another. the 1 thing abut advanced is they dont give nationwide warranty where ever u bought ur part is where u have ur warranty and only there... i am not praising Az cuz i work for them far from it but i do know that whole 5 bad is bull u may get 1 bad in a bunch like every auto parts will have. i know this cuz i also worked for pepboys for 10.5 years.
whatusername
Member
- :
- 02 protege5
pish tosh on that i work for autozone and never heard of having 5 bad alt 1 after another. the 1 thing abut advanced is they dont give nationwide warranty where ever u bought ur part is where u have ur warranty and only there... i am not praising Az cuz i work for them far from it but i do know that whole 5 bad is bull u may get 1 bad in a bunch like every auto parts will have. i know this cuz i also worked for pepboys for 10.5 years. as for the op i would start checking the wiring that goes to the alt. i know on older cars they used a fuseable link and when it burnt out the alt would not charge the batt. also check for a resistance on the cable from batt to alt there should b virtually non or very very low
Do you guys in the USA not recondition alternators?
because i will take a reco'ed alt over aftermarket crap any day... or if you are electrically/ motor inclined... rewind them yourself along with all the other components. It's cheaper, pretty easy if you have done it before.
or get an Auto electrician to do the job for you. In the end... OEM alternators aren't made by Mazda, they are made by an aftermarket manufacturer (i.e. Bosch Hitachi, Mitsu, etc) They all sell Overhaul/ Recondition Kits, with all parts needed.... and they aren't very expensive either.
No.. a Reco alternator is not as 'efficient' as a brand new one (due to the increased core losses from the rewind process), but it is pretty bloody close... and I'm sure its more efficient than cheaper aftermarket alternatives
because i will take a reco'ed alt over aftermarket crap any day... or if you are electrically/ motor inclined... rewind them yourself along with all the other components. It's cheaper, pretty easy if you have done it before.
or get an Auto electrician to do the job for you. In the end... OEM alternators aren't made by Mazda, they are made by an aftermarket manufacturer (i.e. Bosch Hitachi, Mitsu, etc) They all sell Overhaul/ Recondition Kits, with all parts needed.... and they aren't very expensive either.
No.. a Reco alternator is not as 'efficient' as a brand new one (due to the increased core losses from the rewind process), but it is pretty bloody close... and I'm sure its more efficient than cheaper aftermarket alternatives
I dont think it the Alternators that are faulty persay ....The mazda PCM/ECU has an internal voltage regulator.
With out getting into to much detail, the internal regulator in the ECU needs to "see" certain criteria. If it doesn't it won't charge properly.
As I am sure you are aware, alot of autoparts are designed and built to for multiple applications. (able to be used on multiple vehicles)
Unfortunately, what works on the majority, doesn't always work for the Mazda, for example.
whatusername
Member
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- 02 protege5
yea but an alt is an alt is an alt its a protege not a lambo or Maserati so an az alt will work just as good as a oem alt. and if u havent noticed the p5 engine looks identical to the 98+ kia sephia 1.8 engine and since u can use a kia tranny u may b able to use kia eng parts
When my alternator crapped out, I guess it went "full field" as north42g said earlier (I think that's way too high regardless,... can't you fry things at 16 volts?) and it just stayed there. I went to start the car the next day and the battery was dead (I assume from some internal short in the alt.) and I had to boost it. The volts jumped right back up to about 16.5 volts and stayed there so I turned on every electrical load I could think of and there was enough current drain to bring the volts down and turn off the idiot light until I could get it to the garage. After the replacement, everything went back to normal so I assume the problem was only in the alt. itself and not the ECU.
If this happens again I will most likely get one from Mazda for just under $400,... RockAuto has them for $143- $214 with six to choose from. Oddly enough they are all re-manufactured except the cheapest one which is 100% new,... it would come to $193 shipped to me here in Canada.
If this happens again I will most likely get one from Mazda for just under $400,... RockAuto has them for $143- $214 with six to choose from. Oddly enough they are all re-manufactured except the cheapest one which is 100% new,... it would come to $193 shipped to me here in Canada.
