Hi all,
Quick update on RR, typically the starter has been turning over first time every time since We spoke last, removed head light and cleaned both earth connections , checked with multimeter battery pos to engine bracket getting reading of 12.32 which I'm guessing is a bit low , could that cause the problem ? It is a new battery but before I had the car I'm not sure it was used regularly
 
Hi all,
Quick update on RR, typically the starter has been turning over first time every time since We spoke last, removed head light and cleaned both earth connections , checked with multimeter battery pos to engine bracket getting reading of 12.32 which I'm guessing is a bit low , could that cause the problem ? It is a new battery but before I had the car I'm not sure it was used regularly

Hi

Thks for the update

Indeed that’s to low, ideally u want without the engine running 12.6Vdc

What were the readings of volts across the battery posts, was it still 12.32 Vdc, then with the engine running , then Put everything on, ie headlights , heated screen, ac, etc etc and see what the readings are then plse , thks

Give the battery a good charge for at least 24x hours, the CTEK battery chargers work extremely well

I charge mine through the 12s towing socket and also put a battery monitoring mod inside the landy , which allows me to check via Bluetooth what the battery voltage is whilst sitting in doors

Plse let us know how u get on after charging the battery

167ED21E-86EE-4CE1-92AD-6D02207302EA.png
 
thks , have u already got a battery charger , if not get a CTEK

Please let us know how things go after you’ve charged the battery
 
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Yes it was the same across the posts, running 13.8 with everything on 13.6
You need 14.5 to 14.7 with the engine at 2K rpm. Any less and the battery will not fully charge, Lidl do a very good smart charger from time to time for less than £20.
 
Dose this mean my alternator is not charging properly ?

Could just be the battery pulling it down. If you have the cash I'd get a new Platinum one from HTS Spares or similar. If not then see if the local scrappy has one. Stick the biggest one that will fit.

Older alternators had a set point of 13.8V looks like yours might be that. Newer calcium batteries need a higher set point, preferably something like 14.5V. You can change the voltage regulator in the top of the alternator to have a different set point. Go too high and you'll cook an old lead-acid battery though.
 
Thank you for that very useful information about the alternator , I have taken the battery of the car and put it on charge, After about half an hour I did a quick test with the multimeter and got a reading of 12.8. I will leave it on charge now for 24 hours and re test to see how much it drops. The battery is not a year old yet and is a good make and size. I must say now I'm using the car on most days the starter hasn't missed a beat fingers crossed it was a low battery.
 
Thank you for that very useful information about the alternator , I have taken the battery of the car and put it on charge, After about half an hour I did a quick test with the multimeter and got a reading of 12.8. I will leave it on charge now for 24 hours and re test to see how much it drops. The battery is not a year old yet and is a good make and size. I must say now I'm using the car on most days the starter hasn't missed a beat fingers crossed it was a low battery.
I don't know the output of you charger, but the 900CCA battery for the diesel may take longer than 24 hours to fully charge and should reach over 14 volts with the charger still connected.
 
My RR sport is a 2005 SC, the battery is a Yuasa 5000 silver 100ah 900a, the charger is a big sealy not sure of output the readings I gave were with the charger disconnected
 
My RR sport is a 2005 SC, the battery is a Yuasa 5000 silver 100ah 900a, the charger is a big sealy not sure of output the readings I gave were with the charger disconnected
I might be wrong but as a S/C shouldn't it be minimum 920A and 110Ah. Just working on the premise that the full fat Vogue needs as much juice as it can get, so surely a sport s/c also needs it.

Edit: Ooooops just seen @Grrrrrr has said something similar
 
Could just be the battery pulling it down. If you have the cash I'd get a new Platinum one from HTS Spares or similar. If not then see if the local scrappy has one. Stick the biggest one that will fit.

Older alternators had a set point of 13.8V looks like yours might be that. Newer calcium batteries need a higher set point, preferably something like 14.5V. You can change the voltage regulator in the top of the alternator to have a different set point. Go too high and you'll cook an old lead-acid battery though.

Hi

May i pick ur brains plse , interesting reading about the voltage regulator and being able to alter it , this is info I’ve gathered from the D3 forum ,so don’t know how it may compare with the sport

Alternator denso 150 amp
Peaks at 15.8 Vdc
Should settle between 14.3 - 15.2 Vdc
Normal charging rate at 2.000 revs 14.2 - 14.5 Vdc
Shouldn’t drop below 14vdc with everything switched on
Min crank 10.75 Vdc

Voltage control by power control module PCM
Voltage setpoint regulator, controlled by engine management system EMS

Battery 019 950 Cca - 100 Amp

Recommended battery charger CTEK

I Always like to learn new things as I know u guys are extremely knowledgeable
 
Hi

May i pick ur brains plse , interesting reading about the voltage regulator and being able to alter it , this is info I’ve gathered from the D3 forum ,so don’t know how it may compare with the sport

Alternator denso 150 amp
Peaks at 15.8 Vdc
Should settle between 14.3 - 15.2 Vdc
Normal charging rate at 2.000 revs 14.2 - 14.5 Vdc
Shouldn’t drop below 14vdc with everything switched on
Min crank 10.75 Vdc

Voltage control by power control module PCM
Voltage setpoint regulator, controlled by engine management system EMS

Battery 019 950 Cca - 100 Amp

Recommended battery charger CTEK

I Always like to learn new things as I know u guys are extremely knowledgeable
So they have even managed to overcomplicate the alternator:( Useful info nevertheless, I shall bear it in mind and give the new stuff an even wider berth:rolleyes::D:D
Any smart charger will do the job including the one from Lidl, many use the same control chip, you just pay for the name.
 
People like Datatek and Martyuk know way more on electrical stuff than I ever will. My basic knowledge dug up from some chemistry lesson 20 years ago tells me the battery takes a shed load of power when it is empty and then that will drop off as it is charged until when fully charged it just needs a trickle to keep it topped up. So it sounds like they have replicated that with their alternator. Should make the battery last longer although with all that complication you have to wonder if the alternator will.
 
So they have even managed to overcomplicate the alternator:( Useful info nevertheless, I shall bear it in mind and give the new stuff an even wider berth:rolleyes::D:D
Any smart charger will do the job including the one from Lidl, many use the same control chip, you just pay for the name.

Hi

Glad the info is useful for future ref, indeed some of the cteks offer a 12 volt supply , handy when ur doing diagnostics , learnt the D3 are certainally power hungry , also took me ages finding the battery drain, was the memory seat module
 
People like Datatek and Martyuk know way more on electrical stuff than I ever will. My basic knowledge dug up from some chemistry lesson 20 years ago tells me the battery takes a shed load of power when it is empty and then that will drop off as it is charged until when fully charged it just needs a trickle to keep it topped up. So it sounds like they have replicated that with their alternator. Should make the battery last longer although with all that complication you have to wonder if the alternator will.

Hi

Has certainly been a learning curve with these , inc if a denso isn’t fitted it can cause all sorts of issues

My battery will last around 16- 18 x days before it needs recharging , was tempted to fit an AGM battery but believe they don’t like voltage over 14.75Vdc so can’t fit one with the alternator going up to 15.8Vdc
 

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