So just an update. The 150amp oreillys got in failed on the tester and luckily I had ordered the one from amazon, and it came it yesterday. It had the pulley on it unlike the others but it didn't have the black plastic cover on the back. Anyways I took it by oreillys as soon as I opened it up and had thmn test it, and it passed. I installed it in the parking lot and after having them recharge my battery I started the motor just to find my battery light stayed on.

I had them come test the alternator on the vehicle and it showed low voltage. Now my windows and windshield wipers won't work. I've heard things stop working with low voltage so I'm not as worried about that, but I am wondering what could be going on? I never had any issues before replacing the old one and that was only because it's bearings were going out. Any ideas guys?

 

I bought a new alternator from BPUtah a couple weeks back. Put it in and have had no problems whatsoever. I'm sorry to hear about your streak of bad luck. It's amazing how many bad alternators in a row you have gotten. I would have amazon replace it. They have great customer service.

As far as what else could be going on, I have no idea. I'm not sure what could cause an alternator low output besides the alternator itself.

 

Alternator gets voltage thru the battery light from fuse 27 inside the truck. Light should come on at position 2, then go off as truck starts. Indicates low charge voltage. Big bolt in fuse link #1 in underhood box is from alternator to battery, if it was blown you would have no battery charge even with a good alternator. If truck is running at idle, with just engine on, you should expect 13.8 - 14.4 volts DC across the battery. With everything turned on (lights, wipers, AC) would still be like 13.2 volts. If volts drop a lot more under load, the alternator can have a bad diode that is only allowing 2/3 or 1/3 of the capacity to be used. Alternators are three-phase generators, and have a diode array to turn that into DC. One phase can be out, and you have 2/3 alternator. Two phases out, and you have a 1/3 capacity alternator, enough to run truck, but not all the extras like lights and AC. I bought that T shirt with a vehicle that would kill the battery with stop in go traffic, but only on rainy days with defrost, lights, and wipers on. In electrical tems it is not a simple voltage test, it is a voltage under load test that is important.

As for the fuses and fuse links, it just takes one little spark and they can pop. A slipped wrench, a cable dangled against something, etc.

If not at these voltages, you are running around on the reserve capacity of the battery and in less than two hours you'll be walking.

 

When it stops raining here I'm gonna go check the fuses you mentioned savannah. I drove it the 100mile trip back home from school lastnight so I'd have my tools, and I feel like I've milked that battery for all it's worth. Sure do hope I've blown the bolt in fuse or something, because I feel like I'm turning into a professional at replacing alternators.

 

Seem like you got a little too far. Be sure to check volts with truck running, with and without everything you can switch on.

 

Well I finally got it going. Turns out the big bolt-in fuse under the hood was blown, but was still touching enough for a bad read at the battery.

I feel the need to point out again that EVERY alternator that came from Oreillys failed when tested. I ended up using the one off Amazon for $200 and although it didn't come with the black plastic cover on the back it did come with a pulley already on unlike the ones from Oreillys. I went on and ordered another one from Amazon to just have on hand. Plus you can't beat a new working one made in Spain for $200, when the bad re-manufactured made in Mexico ones from all the parts stores I checked averaged around $260.

There are 3 left on Amazon with next day shipping if anyone else is looking. Thanks for the help guys!

 

Hooray!

 

Hi Madlands. Did you get this issue resolved. I have the EXACT same issue. Went to drive to work one day and my '01 Disco wouldn't start. Jumped it and it cranked right up. A day or two later, had the same issue. Jumped it again and then drove to Auto Zone to have the battery and alternator tested. They said battery was fine, alternator was shot.


Bought a new remanufactured Duralast from them, 3 weeks later, same thing. They replaced it, but bench tested the replacement prior to putting it in the truck. The replacement had the same issue (failed voltage regulator). They ordered another from another store, and later that day, bench tested that one and it failed for the same reason again. I then went to my local import parts specialist and bought a refurbished Bosch alternator. I put that in today, drove to Auto Zone to get my money back for the 3rd Duralast, and while I was there, had them test the Bosch while in the truck while it was running. That one failed for voltage regulator too.


So, to summarize:


First Duralast replacement alternator lasted 3 weeks, then failed = voltage regulator
Second and third Duralast replacement alternators were bench tested (not installed), then failed = voltage regulator
Final Bosch remanufactured alternator installed and tested in car (~15 minutes after installing) failed = voltage regulator.


Is it possible that the original diagnosis was incorrect, and I just have a shot battery? I find it strange that all four alternators tested the same, regardless of whether they were installed in the car or just tested on the bench. Anyone have any ideas?


Did getting a new batter finally solve the issue? I did not recently do a coil conversion, btw. Sorry for the long reply.


Thanks,

 

I used a "Parts Player" P38 GEMS Alternator in my 98 D1 that I bought off of Ebay for 135.00 with free shipping. I was expecting it to be a POS, but I read a lot of good reviews for BMW/Audi owners that used the "Parts Player" Alternators. It arrived in a very well packaged box, the alternator itself looked extremely nice with good even paint on the internal blade, and the casing, and it included the pulley. I slapped it on and it's been doing great for 7 months now. I will be buying another one from them if I have another alternator on any of my D2's die.

The FL1 on some D2's is just a flat piece of metal rated at 150AMP, but I believe the earlier ones actually had the fuse looking ones that bolt in. I found Oreilly's sells them for 4.99 for the 150AMP one. I bought two and put one in each one of my D2's and the emergency roadside kit.

The 99 D2 I just got for the steal of the century was actually abandoned and sold because the alternator went out which of coarse drained/killed the battery. The D2 was towed to a LR Shop where it sat for 5 months until the owner forgot about it, and decided to just sell it. I grabbed the alternator out of my 03 D2 parts truck, grabbed a spare battery I had, and drove up, installed the alternator, and the battery, and drove the D2 home 4.5HR without a single issue. I was thrilled to get such a great deal on a really good condition and well maintained D2, but sad that the owner just needed an Alternator and a battery to fix such a nice D2. Well their loss was certainly my gain!!

I took the Alternator that was in the 99, and had it tested, and it basically started to catch on fire during the test so yeah it was ummmm bad lol. It was a 130AMP Bosch unit btw.

My dad back when he drove a 96 Tahoe went thru like 4 Duralast Alternator's. They started to blame his Tahoe, but my dad wasn't gonna have that. When they tested the Alternators it was always the regulator. They ordered him a higher end replacement that wasn't a Duralast (Like a Duralast Gold I think & they paid the difference) and he never had to go back. He also had issues with his 96 Jeep's Everlast battery from Walmart dying. They blamed his Jeep, and one night when it died at walmart he went out removed it, and went inside to exchange it. They said he'd have to come back as the auto center was closed and they must test it to prove it's dead. My dad spoke up and said well my Jeep proves that lady as it won't start hence the reason I'm standing here with your battery. The woman wouldn't back down and said sorry sir you'll have to come back tomorrow. My dad said so your telling me I can't exchange this and I'm basically stuck here? She said sorry but yes sir. He said well I'm outta here and you can keep your damn battery. He was holding it about waist height and he just let go of it completely. It hit the floor and just cracked into pieces... He said goodbye while the lady was saying sir, umm sir.. Then a smartass assistant followed my dad to the door, and said how are you going to start your car now???

He went outside hopped into his Jeep, put it in N rolled out of the parking lot, coasted across the road, and into the Auto Zone parking lot where he bought another battery lol. He didn't go to Walmart for like 8 months after that and that was the last battery he had to put into that Jeep up until when he sold it.

 

Well, I just realized when I posted yesterday that I was only looking at page 1 of this thread. Glad you figured out the problem Madlands. I went out this morning to start my truck and it cranked right up. Finger's crossed that continues. I am going to do some testing tonight with a multimeter to see if there is anything draining the battery when the truck is off and I will check the big bolt-in fuse under the hood as well. Thanks for the info btw Savannah Buzz.

Best4x4, your dad sounds like a great guy!

Thanks