2006 lr3 Battery Light On
 

Hi everyone.
Haven't posted in a while and had to make a new account.
I have a 2006 Lr3 4.0 v6 with 53K orginal miles. Have had trouble free ownership for the past 10 years. It a secondary vehicle and doesn't get a whole ton of use. Have done the EGR valve recently, lower ball joints and new tires recently.
Started hearing a whine and got diagnosed as the alternator. So replaced that. Then recently got the battery light and replaced that yest day. But my battery light still comes on and goes way. Can anyone help me out or point in the right direction? Is the battery bad or bad alternator or something else?
Thank you

most parts stores (i know Advanced does it) will test the battery and alternator for free

Might want to look at the ground cable to the battery. You need to remove the battery, get a mirror and look back toward the right fender behind the fuse box. You will see it attached to a ground lug with a 10 mm nut. This cable gets corroded and does not allow the battery to charge well enough. Make sure the vent in the back of the battery is plugged off and the vent in the front of the battery is vented out of the box. Also look at the connections for the modules mounted on the firewall.

Fumes from the battery can speed up the corrosion process of these cables and connections.

Hope this helps.

Jeff

So i've since replaced the alternator under warranty but battery light is back on. Its a Wilson Reman alternator and a new battery. I've gotten the battery checked and it is fine. The Alternator is charging 14v even and isn't dropping under charge. I've been told that the "regulator" inside the alternator isn't being recognized by the LR because it isn't OE. I have yet to check the fuses and ground cables. Anyone have any suggestions or input ?

You need to check the cables as mentioned. Just do it, not hard at all. You also should remove the positive connector and open up the fuse holder inside that plastic square bit at the positive post. My fuse has A LOT of corrosion. I cleaned it all up and it made a big difference also.

I have the V6 and also had that same issue. I swapped out the battery with an AGM Duracell from Sams Club. Last time I checked, they were still manufactured by DEKA in PA, the only USA battery manufacturer. I trickle charged the new battery until the charger said it was fully charged. I checked the cables and grounds and were tight and as clean as could be. Same. Still showed battery light. I drove it this way for some time. I think my GAP tool said it was 13.4 ish volts. In an effort to sort out my transmission shifting issues, i thought i'd replace the alternator to make the truck happy. It's all tied together, so one less thing for it to complain about. I replaced the alternator with an AC Delco from Rock Auto. It was the only brand that claimed to have windings replaced along with the bearings, diodes and regulator. Other brands just recon what was wrong with the core they are repairing. No thanks. Battery light disappeared but showed only an additional .3 volts over the one I replaced!!! But it was enough to extinguish the battery light. I've never seen the alternator charge any more than 14.1 volts. Anyone else only show 13,7 volts as a typical charge rate?
In your case... Is it a brand new battery? Not just a different or reconditioned one? Did you charge the battery before you installed it? Brand new batteries should be charged before putting into service. If the battery and cable connections are ok, I would look towards the alternator. BTW, the acorn nut for the the ground to the chassis behind the fuse box is a 13mm, not a 10mm. You should use a deep well, 6 point socket as a standard depth does not extend to the bottom of the nut because of the rounded acorn top.