AGM battery out of my Range Rover ...

[Porthandbuoy]

In the case of my Freelander 2 if you press the key fob just once to lock it there is still a significant battery drain. Press it twice to immobilise it and battery drain diminishes. Not a huge problem wen the battery is newish, but worth remembering when the battery is older and the cold weather creeps in. I get about 6 years out of a standard lead acid battery on my vehicle.

 

[Refueler]

Given the complexity of modern cars, surely it's time for all cars to have a battery that can be allowed to go flat - maybe it should be LiFePO - for the "domestics", and a dedicated battery for starting. Bad news for those who come out to airports to jump-start cars after a few weeks away, but good news for the owners.

As cars and tech has evolved - more and more add-ons are to a car that require power to maintain the user data / settings ... its fine saying its only a few mA to hold the settings of your radio ... but then you have the alarm system with surround capability ..... in fact I'm having trouble remembering all the stuff that is kept 'stby' when car is parked. But its mind-boggling on some.
I purposely - even though it would be brill where I live - do not use the built in timed Webasto system to preheat the car .. I err on the side of caution .. so that 4.4L diesel lump can still pull from the battery !

Pal of mine with his Voyager used to use it ... and then it didn't take long before his battery said ****** !! and that was only a short ON each morning to preheat car before going to work.

 

[Refueler]

In the case of my Freelander 2 if you press the key fob just once to lock it there is still a significant battery drain. Press it twice to immobilise it and battery drain diminishes. Not a huge problem wen the battery is newish, but worth remembering when the battery is older and the cold weather creeps in. I get about 6 years out of a standard lead acid battery on my vehicle.

Even Clarkson remarked about the power use on a Range Rover ... he is an owner and fan of the same RR as I have - L322 4.4 TDV8 ....

He moaned about the timed power down etc. Its not only the interior lights that take ages to go out if you just open and close a door ... the whole electrical system energises when you open the door ...
Close door and you can stand there ages waiting for car to power down again..... even when you lock the car.
I know that some do speed up this by use of the key fob ... maybe mine will .. have to check.

 

[fredrussell]

Sorry, me again. I just can’t accept that a ‘healthy’ modern car won’t start after a week unused. Have a read of this thread…fullfatrr.com - View topic - [SOLVED] Testing Battery Drain Instructions Help
…it’s on a RR forum. OP had same problem as you - finally traced current draw to a faulty component, as did lots of other RR owners on that thread - not one of them says it’s normal for car not to start after a few days. Do you have a clamp meter? Very easy to test what current drain is without disconnecting pos or neg lead.

 

[Refueler]

Sorry, me again. I just can’t accept that a ‘healthy’ modern car won’t start after a week unused. Have a read of this thread…fullfatrr.com - View topic - [SOLVED] Testing Battery Drain Instructions Help
…it’s on a RR forum. OP had same problem as you - finally traced current draw to a faulty component, as did lots of other RR owners on that thread - not one of them says it’s normal for car not to start after a few days. Do you have a clamp meter? Very easy to test what current drain is without disconnecting pos or neg lead.

Its interesting actually as talking to a mechanic - he asked what car started like when the Jump Pack was connected ... and I said as if nothing wrong ... not the normal sluggish when battery flat and jump pack is trying to start car .... he commented that possibly the battery was fine - but immobiliser momentary fault ...
Anyway - I'm due to travel again soon ... will find out then.

 

[jamie N]

"Buy British and free your automotive electrons from the captive restraint of efficiency."
Or, as it's been stated over decades, Lucas electrics don't use electrons, they use smoke, so you know that when they fail, they simply let the smoke out.

 

[duncanmack]

"Buy British and free your automotive electrons from the captive restraint of efficiency."
Or, as it's been stated over decades, Lucas electrics don't use electrons, they use smoke, so you know that when they fail, they simply let the smoke out.

It's true. I still have a Joe Lucas fact sheet about that.

 

[OCuea]

I use a LR Disco for towing plant at work (Building trade). It can be left for weeks and amazingly it starts right on the button. Interestingly, the newer one we bought to replace that tired old TDV6 ground to a halt when the crankshaft snapped in half (seriously!) - a very common thing apparently. The local LR specialist (Landapart, Woodbridge) told us that was the 14th one they had dealt with that year (2024) with this fault. So I’ll have to decline your invitation to buy a Land Rover.
Crank shaft snapping

Oh my. I know the world is going to pants, but to have a CRANKSHAFT break! As is a part of the engine that should be the strongest part? Wtf? my series 3 needs some tlc but is fantastic - do anything, go anywhere, camel trophy stuff, rebuilt from chassis up (but can’t have a conversation with passenger) hence bought a discovery 1 ES model, JOY dual climate control, AC , cruise control, leather, coil springs, diesel etc had it maybe 20 years and everything fixable by me. Modern cars have some great attributes but servicing or fixing scares me - and a broken crank , come on!

 

[OCuea]

Why do modern cars not have built-in PV panels, maybe on the roof? I am aware that they don't do well if you park in a dark place. My experience was after leaving my car for five weeks. The AA man said that I was the third that he had attended that morning for the same reason. It was his suggestion to fit the small PV panel, which now sits permanently on the dashboard.

I attached a rather large solar panel to the roof of one of my cars. Cheap as chips. Solved many problems. So your question is very pertinent to the industry - will they listen?

 

[OCuea]

I always have one of those lithium battery jump start battery things (size of a tissue box) in the boot these days because modern cars have so many drains. Those little jump packs are amazing.

 

[William_H]

Hi Nigel. I think you were right to replace the battery. Even more so if you have a use for the old battery. Yes capacity for low drain is a different requirement to high current engine start and probably the old battery was failing in the high current delivery part. Certainly when a battery in a car or boat starts to seem sluggish in cranking it is time to consider replacement. You might get a few more months of service but actual money saved will be small. Inconvenience of a battery failure especially in a car is not worth the savings. I don' think it worth suspecting and exploring current drains when parked unless the new battery has same problems.
Re replacing the battery, it is quite easy to attach another 12v battery to the battery leads so that there is always power to the car when changing the battery saves a lot of trouble. Re actually removing and refitting the battery in your RR you have my sympathy. Lets hope your mechanic is younger and bigger than you. ol'will

 

[OCuea]

Hi Nigel. I think you were right to replace the battery. Even more so if you have a use for the old battery. Yes capacity for low drain is a different requirement to high current engine start and probably the old battery was failing in the high current delivery part. Certainly when a battery in a car or boat starts to seem sluggish in cranking it is time to consider replacement. You might get a few more months of service but actual money saved will be small. Inconvenience of a battery failure especially in a car is not worth the savings. I don' think it worth suspecting and exploring current drains when parked unless the new battery has same problems.
Re replacing the battery, it is quite easy to attach another 12v battery to the battery leads so that there is always power to the car when changing the battery saves a lot of trouble. Re actually removing and refitting the battery in your RR you have my sympathy. Lets hope your mechanic is younger and bigger than you. ol'will

I used to use use long croc clips to keep power to vehicle but found an OBD device somewhere that simplified things. Just replaced a stop start battery on a 2024 vehicle for a friend with no probs (surprising) . If I can do that, anyone can change a battery.

 

[Sea Change]

I always have one of those lithium battery jump start battery things (size of a tissue box) in the boot these days because modern cars have so many drains. Those little jump packs are amazing.

I wonder how they work... I had one which said it was an LiFePO4 battery inside, which normally can only supply 1C current, yet it was able to jump start a large diesel engine. I presume it was bypassing the BMS? Which kind of breaks all the rules for this type of battery.

 

[OCuea]

I wonder how they work... I had one which said it was an LiFePO4 battery inside, which normally can only supply 1C current, yet it was able to jump start a large diesel engine. I presume it was bypassing the BMS? Which kind of breaks all the rules for this type of battery.

I don’t think mine is LiFePO4. Cost approx £55. Had it a few years. Has started big diesels and little performance petrols in Winter (when the battery really should really have been replaced). Actual capacity in amps per hour is low, so assume some DC to DC booster is involved. Don’t know, but it works and has saved me £100 on a new battery a few times.

 

[Refueler]

Battery changed ... all good now.

Li jump pack carried just in case !!

Todays cars annoy me .... on this battery lark.

I can remember days when I could listen to the car radio all day long and still start car ... but now ? I hardly ever have radio on without engine running - having had various cars fail to start after a few hours of music.

 

[greeny]

Wish I could find a way of permanently disabling the stop start on all my cars. Most of my driving is short distance with lots of stop starts. Can't be good for the battery. The disable buttons only work for the current journey then resets itself. PIA. Spoke with Landrover, Mazda and Nissan about it and all of them say it is possible in software but they are not allowed to do it. Even the mini in UK does it. At least my boats don't do it, yet.

 

[Refueler]

Wish I could find a way of permanently disabling the stop start on all my cars. Most of my driving is short distance with lots of stop starts. Can't be good for the battery. The disable buttons only work for the current journey then resets itself. PIA. Spoke with Landrover, Mazda and Nissan about it and all of them say it is possible in software but they are not allowed to do it. Even the mini in UK does it. At least my boats don't do it, yet.

Its not only Stop Start ... DPF as well ... if you don't do regular long journeys with good rpm on engine - the DPF just fills up and then the dreaded 2000rpm for 10 - 15kms to try purge it ...

My RR ended up with 102gr !! It shut down so all I had was Limp Home mode ... OBDII couldn't fix it because it was over the 60gr .. had to have local Toyota dealer open - inject and blow it out ..... JLR reckoned not possible.
When JLR had car week after Toyota to replace a few sensors - they scanned and found the DPF was not registering more than 2gr !! They'd never seen one so low ...