Range rover sport tdv6 57 plate completely dead

[RRS man]

Hi there piston heads ,wonder if anyone can help me,I have a 2008: tdv6 RRS and the battery is fine but completely dead no lights on dash no electrics at all . It was driven home and parked on the drive seemingly all ok and then a few days later tried to start and nothing ?? Cheers RRS man.

[finlo]

How have you determined that the battery is fine?

[RRS man]

No I haven't checked battery yet as I only replaced it 6 months ago,but I will check before doing anything and reply ,cheers Pete.

[paintman]

Electrically complicated vehicles which can play up if battery voltage is low.
Never assume the battery ISN'T the problem.
Fully charge with a battery charger & see what happens.
Also check the battery connections are tight & clean.

[RRS man]

Thanks paintman. I left on overnight charge and retired her today all running good ,but shortly after a run out got HDC fault and special systems off and park brake fault ??? After switching on and off all disappeared but reapears when been used again ?? Confused.com !!🙄🙄

[finlo]

RRS man said:

Thanks paintman. I left on overnight charge and retired her today all running good ,but shortly after a run out got HDC fault and special systems off and park brake fault ??? After switching on and off all disappeared but reapears when been used again ?? Confused.com !!????

Low voltage play's havoc with these fancy systems, so i'd be looking at both the battery and alternator.

[AdeTuono]

They all do that sir. Switch it off and switch it back on again.

[paintman]

finlo said:

RRS man said:

Thanks paintman. I left on overnight charge and retired her today all running good ,but shortly after a run out got HDC fault and special systems off and park brake fault ??? After switching on and off all disappeared but reapears when been used again ?? Confused.com !!????

Low voltage play's havoc with these fancy systems, so i'd be looking at both the battery and alternator.

Get both checked. There may be a fault in either or both.
If the alt is faulty it won't do the battery any good & if the battery is faulty then it won't do the alt any good. Alternators are designed to run the vehicle electrics and to keep a good, charged battery topped up not keep recharging deeply discharged ones.
Not just my opinion: https://www.optimabatteries.com/en-us/experience/2...

Whilst the battery may only be 6 months old it doesn't follow that it's not defective. I had 3 replaced under warranty on my own RRC a few years ago. No issues with the car's electrics. Would be fine for around 9 months then once into cold weather wouldn't hold charge.
Lion brand from eurocarparts. I'm trade & I think the chap behind the counter thought it was customers' cars as he cheerfully told me they reckoned to get around 1/3 of them back in the warranty period.
A Halford's battery has been fine to date. If you do go to Halfords try & find a friend with a trade card as the battery discount is substantial.

Also get a diagnostic to see what fault codes are stored & worth checking to see if you have a parasitic battery drain - as in something not going off when it should or being turned on by exterior sources.

Edited by paintman on Wednesday 2nd January 10:17

[RRS man]

You were right there paintman ! Battery output was 11.9 volts ,so although engine cranking and starting ok I think ECU detecting output voltage too low ,have ordered a new Yuasa battery and will try that and see what happens .

[paintman]

Fingers crossed!