I was warming it up a couple minutes in the drive, went back in for 2 minutes, came back out, was off but radio still on with climate control. It wouldn't crank, just clicked. took the other car to work. (because if you have a land rover, you need another car too!)

A couple days later when I finally got to look at it again the battery was mostly dead, only gave like two cranks. I know the battery was 6 years old, and had recently dies, so I went ahead and replaced it (with optima gold) and it has been fine for the week since.

But I can't think of why it would die while running from a battery issue. The alternator is 6 months old.

Should I keep an eye on the main relay or something?

 

Ehhh.....I trust you have an Ultra Gauge or something you can keep an eye on the voltage. ? Do that for the next couple days and report back.

 

I had a jeep that the battery died on. It wouldn't run even with a good alternator. Even after jump starting.

UG is the way forward if you don't have one.

 

If the alternator is bad or disconnected, the battery will keep it running for a long time... then die and leave you stranded on the side of the road, in a suit, on the highway your friends who all drive new cars on have to travel... oh, I am reliving it... I had a newish alternator die and had to have it rebuilt. I had to actually buy a battery just to have enough juice to get home.

Also, if your wires on the passenger side come disconnected and lay against the exhaust, they can ground and leave you with no power brakes, steering, or light/hazards on a two lane highway in a construction zone with a steep dropoff, 50 miles from the next town at 2am... oh, there I go again...

If it isn't the alternator or just a bad battery (but I have never heard of a battery stopping the vehicle mid-run), you can check the source of the drain with a meter on your fuses when the key is out.

 

I have a bluetooth OBD2, my volts are around 13.9.
No problems again yet, but I'll let you know

 

No idea what it was the morning it died?

 

Well it started right up, but I did turn on the heat and heated windshield defrosters. But no.

 

Update: Been monitoring with my OBDII bluetooth thing. It always has good voltage when I come out in the morning, and is always upper 13s at idle. EXCEPT...
A couple times I have come back out to find it running at 11 volts at idle with the battery light on. I haven't been able to catch when or how it does it. In the situation if I tap the accelerator once, it immediately jumps back up to proper charging, then stays there even at idle. And it's always fine when driving.
So is the voltage regulator in the alternator going out? It's only 6 months old!

 

if this is happening and your idle is correct then you should never he seeing 11 volts. So hopefully it came with a warrenty.