I was going to make this installment #3 of "Maybe it's supposed to do that...", but I'm pretty sure it's not supposed to do this.

Over the last few days we went from having a cold snap to a warm snap and back to a cold snap. It's Kansas, after all. I noticed that while running the climate control system, I started to get a very distinct whine that would go away when I turned climate control off. The whine is new. I remember seeing somewhere (on this forum most likely) that the heated windshield puts a pretty good load on the electrical system - so yesterday I sat in my garage (door up this time, and no garden hose) with the LR3 running, GAP tool plugged in and started toggling the heated windshield.

The door drivers door was open so I could hear the whine better, so the dome light was on. When I hit the button for the heated windshield, the whine became a growl, the RPMs dropped from 744 to 580 and the dome light dimmed. Volts reported by the GAP tool also went from 13.9 to 12.1. As I revved the engine, volts increased back to 13.9, dome light got brighter and the growl got louder. The reverse happened when I let off the gas, and then all returned to 'normal' when I switched off the heated windshield.

Have I correctly diagnosed this as a failing alternator, or is it 'supposed to do that'? Wading a bit deeper into the weeds, is there an upgrade to the OEM alternator? For example, I installed a 180v alternator from a Nissan Quest onto my Nissan Xterra as an upgrade to the 160ish that was OEM.

Thanks,
J

 

When my alternator went out it started as a whine, then howl then fail so exactly the same as yours. Mine finally failed while driving and I lost engine power had to limp to my Indi mechanic at 20 miles an hour luckily I was only 10 mins away at the time, would not of liked a fail on the freeway or anywhere out in the wilds.

 

Thanks for the reply - good to know. Looks like a new battery is in order too. With the key on and engine off, volts off the battery according to my GAP tool are only 12.1....then 11.9....then 11.8...

 

Almost exactly what happened to mine about 2 moths ago with the same noises and volt readings. Except when mine finally went it took the battery too. Only about 5.6 out of it...you may still be able to save it. I was advised to disconnect it until alternator replace so perhaps something you may consider. New alternator and battery (was only a few months old so replaced under warranty) and she is good to go.

 

Thanks - that lends a bit credence to what I am seeing and hearing. My local DIY club gets a parts discount at the Autozone near them, so I went there this afternoon to price an alternator and battery if need be. The helpful young man behind the counter hooks up his battery computer thingy to my LR3's battery and says, "You have a good strong battery and your alternator is fine."

I am replacing the alternator Friday morning in spite of him - but I wonder if there is anything else I should be looking at as well...?

Av8r - you wouldn't happen to be on Stromtrooper, would you?

 

Anything Autozone (or your run-of-the-mill parts store) says I would take with a grain of salt.

Have had bad or clearly wrong advice more than once.

 

Dv8er - not me on Stromtrooper.


Agree with DavC and had same bad advice from similar type places. Feedback you get from the forum is trustworthy and from folks with lots of LR experience. Your symptoms are nearly identical to mine and that of many other posts resulting in same fix...new alternator. For what it's worth, RockAuto.com for parts is a good source. Great selection of OEM new, OEM rebuilt, and non-OEM parts. Very quick order process and shipping. I bought my alternator and front brake kit (new rotors, pads, and sensor). Both shipped within hours of order and delivered in 48 hours for a very modest shipping cost. Easy return label process in same box for alternator core. Just my $.02.

 

Well, autozone wasn't diagnosing bad alternator bearings. All they check is if it is producing a certain voltage. The heat being generated by the bad bearings, is slowly killing the rectifier. Eventually it will no longer work at all.

 

x2 on all of the above. The kid from Autozone seemed perplexed when I pointed out the noise it was making - it forced him to break script, and he was out of his comfort 'zone'. Anyway, I did end up going with Rockauto - even with mailing back the core, I get a Denso for cheaper than the Duralast at Autozone or the Remy from our local hub - so that is a win! It only needs to last 3 more days...

 

Your original symptom (whine with climate control on) may not be related to the alternator.

Try leaving climate control on and turning the AC off and see if the whine goes away. If so, it's possible the refrigerant in the AC system is low, likely due to leaks in the rear AC lines. This produces a whine that changes with engine speed and will go away as soon as AC is off. I had my AC recharged as part of another repair and the noise went away for a while, but has gradually come back. I'm guessing there is a small leak somewhere, but that's way down on the list of next to fix.

Agree with the comments on the alternator, it usually goes "bad" all at once after making noise for a while, and usually involves some amount of smoke and will toast the battery as well. Mine makes a harsh whir audible in the cabin above 2k rpms for a couple minutes after start up, but minimal noise after that. Seems like it's only a matter of time as well.

Oh and I found out I have the original Hitachi compressor and it's been sounding rather buzzy lately. Hooray for Land Rover ownership!