Battery Light + Whine + Low Idle + New Battery

TT4RLtdV8

TT4RLtdV8

New member
Evening Gents.

After searching and reading a few threads on a battery light issue, I'm looking for a little clarification/direction.

2006 V8 AWD. 217k. Timing belt and water pump done at 215k, serpentine done at 208k. I have NOT done the secondary air bypass, but I do have the kit in my garage ready to go.

After having my Toyota dealer install the timing belt and water pump, I noticed in the mornings the truck would make a whirring sound with what I thought was a fan clutch engaging and disengaging. It would not do this when the truck was at temp.

I got a battery light a few nights ago. Took it to Autozone and had them test it and the alternator. The battery wasn't doing so hot, and the alternator came back fine. Slapped a new battery in with 750 cold crank.

After putting the new battery in, the battery light did not go away. The whirring has gotten more noticeable. Video here.

Gut says alternator. But I've also seen posts regarding ground issues at the fender, alternator, or ECM.

Electrical testing shows the battery at a 12+ V reading, and when running and with throttle it jumps to 13-14, so that says the alternator is functioning, but the whirring tells me it is on its way out? Or is it something completely different like a dying powersteering pump or... something else?

Thanks for your time and opinions.
 
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Unplug the alternator and see if noises change. If yes, then bad alternator. I'm pretty sure it's bad alternator. Also check to see if that power steering pump isn't leaking down onto that alternator.
 
djkurious said:
I would suspect a bad alternator being the battery light is on.

Does the voltage drop once the whine starts?
Click to expand...



Nope. I almost wish it would have, would have saved a post and I’d have a new alternator on the way by now!


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D. Le said:
Unplug the alternator and see if noises change. If yes, then bad alternator. I'm pretty sure it's bad alternator. Also check to see if that power steering pump isn't leaking down onto that alternator.
Click to expand...


Never thought about it leaking. These noises / issues started after Toyota put the timing belt on. Do you think something could have happened on the reinstall that caused the leak -> subsequent alternator failure?


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Went through something similar for about 9months. Had a really weird whine/groan that thought was the power steering pump. Would come and go and usually only happen during the first start of the day. Fast forward and I'm about 2 days away from buying a new PS pump and the battery light comes on. Alternator the whole time.

Just for funsies, I took the bad Alt to Autozone to have it tested and it PASSED. So take that for what it's worth.

I also replaced my acc belt with the alternator and made things a lot more quiet. Guessing the old one was stretched. Maybe the new one put enough more tension on the alt to kill off marginal bearings?

Went with a Rebuild from Partznet and am happy.
 
I used to work at AutoZone, while in college. The alternator test is not full proof. There has been several occasions in which I tested a bad alternator that tested good. In many cases a bad alternator works better when cold (on the bench test) and when the engine first starts (higher rpm for minute or two). In this case it would typically be a bad voltage regulator. On the other hand if the diodes in an alternator fail then it will always test bad.
 
TT4RLtdV8 said:
Never thought about it leaking. These noises / issues started after Toyota put the timing belt on. Do you think something could have happened on the reinstall that caused the leak -> subsequent alternator failure?


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Click to expand...

Were you able to unplug it? Might have access through the passenger side apron.
 
D. Le said:
Were you able to unplug it? Might have access through the passenger side apron.
Click to expand...



Not yet. My work week has been keeping my in front of a computer all waking hours instead of my toolbox. Friday I’ll tear into her. Have a new alternator just in case, and it’s time for plugs, oil change, and secondary air bypass.


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My truck did the same thing when I used a winch for too long. It just smoked the alternator and the light came on. Once I slapped in a new alt, everything was good.
 
Well. My alternator arrives today. Which is good because my truck died on me last night driving home. Luckily it died in my neighborhood walking distance from my house. Got it to start with a quick battery charge and got it back to my garage.

Thanks for your input all. Turns out the best way to confirm a troubleshooting exercise is to experience a failure.


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Alternator swapped. Started at 7:30 pm ended at 9:22 - had a buddy and a half help (the half showed up to tighten nuts on the new alternator, steal a beer and leave).

Full write up when I’m not on my phone.


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hope you had the battery charged by a charger first, dont want to ruin the new alternator that fast with a dead battery.
 
Write up time... here we go.


After researching alternator swap methods on this forum, three main methods became apparent.

Method 1: Pull the fan and fan shroud and pull the unit from the front.

Method 2: Pull the passenger tire, power steering pulley, pump, and skid plate, then pull it from the side.

Method 3: Pull the tire, skid plate, and the sway bar, go from the front-ish.

We did a hybrid of methods 2 and 3.


The truck entered the garage at 7:30 PM EST. We (my buddy and I) immediately put it on a jack stand and pulled the tire. We removed the coolant reservoir up top, and removed the belt.

Then, we pulled the wheel-well (spelling?) liner and started removing the hardware that held the alternator to the block.

Heads up: The bottom-most hardware widget is a bolt. It is very long, and there is a piece of plumbing directly in front of it. Hard line + clamp into a rubber line. This was the worst piece to remove. We ended up going over top (when laying under the truck going towards the sky) to remove it with a ratcheting wrench. In a full toolbox of equipment, this was the only tool that could remove the bolt with the clearance available. This is your 14mm bolt.

Then, from the top (again, engine bay looking towards the ground), we removed the two 12mm nuts using a combination of sockets and fingers. Once these bolts were removed, and the alternator was attached by the lone 14mm stud, we removed the electrical connections and their two 10mm hardwares. One is a bolt that holds a harness to the alternator enclosure, the other is a nut under the plastic cover that holds the line to the alternator plug.

Then, and this is the fun part, we removed the passenger sway bar bracket and let it hang. This was the only way we could have removed the alternator without serious shenanigans. You also need to remove the power steering pulley. 17mm if I remember correctly. You will need to place a socket extension or some other solid long something in the pulley to add an opposing force to your wrenching the nut off. We did not need to remove the power steering pump.

**Break for beer**

We then took the new alternator and fished it between the sway bar and the plumbing to get it into the cavity where there is plenty of room to maneuver it onto the stud for placement. This was hard only because the alternator is kinda heavy and you have to do some wrist/finger gymnastics to get your hand up in there.

Once the new unit is on the stud, finger thread the hardware on before tightening. The bolt was done with fingers until friction became present, then we went back to the ratcheting wrench to place it with finality. The other two nuts were completed with fingers and sockets. 12mm.

Once the alternator was secured, we plugged the electrical connections back in (the little 10mm bolt that holds the wiring clip to the alternator body was a ***** on wheels. It takes some finesse to get it placed right, and the right sized tools to get it secured. I'm embarrassed to admit this was the hardest part of the project, all things considered.)

Once secured to the block and belt routed, we jacked up the passenger lower control arm to replace the sway bar. Once assembled, we replaced the belt, then the skid plate, and then the tire. I forgot about the well liner during this process.

Don't forget about the well liner. Real annoying to put back once the tire is on.

That's it. Once everything was put back, the truck fired right up and the battery light, and the whine, went away. Repair time stopped at 9:22PM EST. Total time spent: One hour and fifty two minutes.

This is a two person job if you can swing it. Really helps having someone up top while you're under the rig.

Thank you to everyone who provided input on my original question, You seriously helped shorten the time between trouble shooting and part ordering. The total failure last night confirmed everything, but your input led me to ordering my alternator when I did, just in time for tomorrow's snow storm.

Happy to answer questions if there are any, or provide clarification.

(I'm going to do the spell check/grammar edit tomorrow. I'm pretty beat but wanted to get this down in writing before I went to bed).
 
riceandpho said:
hope you had the battery charged by a charger first, dont want to ruin the new alternator that fast with a dead battery.
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Totally did. In this battery cluster f***, I made sure my new alt had a fully charged unit to play with. Great point though, nothing worse than slapping on a new alt then having it work to death charging a near dead battery.


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iim surprised you didn't try upgrading the wires while everything is out. just a new positive lead at 4 gauge minimum should help with the added accessory, I do 1 or 0 gauge. and also new grounds. basically the big 3 with the battery out so you have extra room.
good thing on the 4.0 v6, its so easy to change the alternator. just take out the battery, take out the belt and 3 14mm bolts, unclip a few things and move a harness bracket out the way, I think a total of another 5 10mm bolts. also the engine cover.
so what alternator did you end up using? I still have the oriley special just incase.
 
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