Good morning all, I have had a call from a friend to pick him up stranded, he was driving back last night when his lights briefly flickered then an instant and total shutdown, luckily he managed to steer in to a gateway, nothing left at all not even hazard lights, it can't be winched as it is of course in drive, has anyone come across this before? Many thanks

Sounds like the alternator has packed up.

You should be able to winch it but you have to put it in Neutral. There is a release under the centre cupholders, details in the manual, not sure if it releases it from D though as it is usually used to release it from P. There is nothing that can't be fixed with a hammer😜😜
FFRR 4.4 SDV8 Autobiography Santorini Black.
KIA E-Niro 4+
2021 Discovery 5 D300 MHEV commercial

Thank you, would alternator fail drain the battery instantly? The AA on on the way!!

A flat battery will occur within a very short time if a diode fails short circuit.

Do alternators on this engine show any warning signs before they fail ( weeks / days and not seconds) or have an average mileage fail distance? 2012 TDV8 Vogue (L322)

Thanks for your help on this, AA man thinks it's a short at the back of the alternator, apparently access is restricted from above so he can't tell exactly, on a recovery truck now, it drained his power pack instantly then when ho hooked her up with jump leads there a smell of burning so switched straight off, I will let you know the outcome. Cheers

I reckon alternator has gone and taken battery with it. Always put a new battery on when a new alternator is fitted. 019 AGM on a 2011 4.4 Gone to a good home: 2011 4.4 TDV8 Vogue SE Buckingham Blue with Ivory and clear glass = "Rory"
2025MY Defender D350 90 in Silicon Silver on coils
1974 Series 3 Lightweight = "Millie"
Many, many other Landies over the years
My preferred specialist: www.glenrands.co.uk
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The power diodes used in the brand of alternators that LR use are avalanche (Zener) diodes used to prevent excessive over voltage, a condition that can occur if for example the battery becomes disconnected while the engine is running. These diodes have the characteristic that once their trigger voltage is reached they reverse conduct, thereby causing an instant reduction in voltage. The problem is that as the diodes age, which is accelerated when they've been working close to their current capacity, is that the trigger voltage lowers eventually getting down to battery voltage at which point one or more reverse conduct causing an almost dead short. Because LR attach the alternator's output cable to the starter cable, the much higher current capacity of the fuse on the starter cable won't blow when the alternator diodes short circuit back through the windings.

Some other alternator manufacturers use normal diodes for power diodes and use avalanche diodes in the regulator circuit to handle over-voltage without causing a short circuit of the battery. I fitted a separate power cable with an appropriately rated resettable circuit breaker to the alternator of my previous D4 but haven't yet fitted one to the L322.

Just to update, he picked her up yesterday and indeed ''twas the alternator" they checked and said battery was fine so didn't change it, £600 bill apparently they are very awkward to do, thanks for your input.

They are awkward to replaced but a £600 bill is actually pretty reasonable  Got - 2017 SDV8 Autobiography in Loire Blue
Had- 2008 TDV8 Vogue SE in Java black
Had - 2007 S/C in Stornoway Grey

Parts are cheap on these engines (it's a Ford!) - it's the labour involved in fitting them that's expensive! I'm sure the garages actually prefer working on D3/4/RRS where you can just lift off the body to get at everything?
I'm going to need some work done on the aux belt system and it may be just cheaper to get the alternator replaced while they are at it. 2012 TDV8 Vogue (L322)