Some questions for the board...
 

I don't drive my LR3 very often....and it'd been about 2 weeks since the last trip (yesterday). I go into it to run an errand and just to drive it....and it wouldn't crank. Dead dead dead. No clicking even.

So I jump started it. I drove it around the block. Turned it off; tried to start it. No. Jumped it again. Drove it farther this time and then cycled it. It started but struggled.

So it seems as though the battery got drained....idk, maybe I bumped the stereo power knob and didn't notice....idk? Good thing it's an AGM battery because I can probably bring it all the way back (to life).

Here is the real question: My rear Parking Distance beeper is not turning on. Could this be related to the battery? Did I blow a fuse? Any thoughts? I'll check the fuse tomorrow but I thought I'd ask if anyone has experience....

I guess nevermind...I place this in the in the "because it's a Land Rover" category.

I pulled the fuse for the PDC. I tested it and it showed good. I changed it out anyway. I fired up the Rover and put it in reverse and heard that familiar chime. Working again.

Could be a (Likely) sign your alternators going out.

No way....more likely there was some corrosion on the fuse-interface and removing it loosened it up.

My alternator was changed about 30k Miles ago.

Was referring to your battery drain.

"A car alternator recharges the battery and powers certain electrical systems. If your alternator has a bad diode, your battery can drain. The bad diode can cause the circuit to charge even when the engine is shut off, and you end up in the morning with a car that won’t start."

An alternator can go bad a week after being installed....

Yes....most likely I bumped the radio power button though and it drained without my knowledge. I had all three tested (batt, alt, starter) and all checked out "good." I just need to drive it more and charge that fcuker up!

I could've been out there dickin' around with my IIDTool and then not driven it for a few weeks and that combination killed the batt. Good thing it's an AGM!

The fuse for the rear back up sensors/TMPS is not integral to the operation of the vehicle... I've had mine removed for a few weeks now...


I'm pretty sure the radio power button is operational when the truck is off... do you leave your keys in the truck when not using it?

Yeah I think the fuse issue was unrelated to the batt.

The radio button does in fact come on with the truck off. I've had that happen in the past; I'm inside looking for something and I bump the power button but the volume is low and I luckily notice it before I walk away. Maybe this time I didn't notice it!

I don't leave my keys in it.

With the LR3 running meter the battery it should be 14.4V or higher. Turn off the LR3 and hold the meter on it, if it drops to 13.0, 12.5, 11.9, all the way down to 11.2-10.9V that battery is toast. Does your LR3 idle high often? If it does its trying to charge the battery.

I just changed my 6/13 dated battery out on Sunday. My wife said the LR3 wouldn't start, then it did, and once it started all kinds of faults popped up (due to the voltage dropping low as the starter was engaged causing Can Bus comm issues). I metered it as it idled high and it was crazy high like 15.2V, then once turned off it went down to 10.9V within maybe 30 seconds to a minute. Swapped out the battery with an AGM model, and metered it again after it was shut off. Stayed at 13.8V for 5min. Also it now idles normal vs racing as it tried to charge it.

It takes a fair bit of time to charge up a battery from dead, and 15V is not unheard of while it is doing so. You really have to drive it for a bit to get it back to normal voltage. I see 15V when I don't drive my truck for a week or two. You'll see the charging voltage start to taper off down to around 13V or so when it's going back to normal. It's after a long drive when the battery still drops down below 12V (with no other drain) when you should be worried.