I’m having issues with my 2010 Range Rover 4.4L Diesel – the battery keeps draining, and the car won’t start after a day or two. I’ve done a bunch of troubleshooting but can’t seem to figure it out. Hoping someone here might have some ideas!


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What I’ve Tried So Far:

1. Starter Motor:

The starter was struggling to crank, so I replaced it with a brand-new Denso unit. (Accidentally destroyed the old one cleaning the contacts)

While I was at it, I set up a solenoid trigger bypass with a relay directly connected to the battery.

The car ran great for a bit, but the same starting issues came back.



2. Battery:

Swapped the battery for a new AGM one in the last year.

This helped a little but didn’t completely solve the problem.

Load tested at 1000+ CCA yesterday.




3. Current Draw Test:

Checked the current draw with the car locked for 30 minutes:

It was pulling about 300mA.

I pulled the Bluetooth module fuse, and the draw dropped to 80mA.


Opened up the Bluetooth module and replaced the capacitors (Bluetooth started working again after this – it wasn’t working before).

After this fix, the current draw stayed at 80mA, so I thought I’d sorted it.



4. Charging System:

Fully charged the battery with an AGM charger, and the car started perfectly the next day.

Took it on a 2-hour round trip, but the day after that it started for a short trip to the shops and wouldn’t start again – just a solenoid click.

Used a lithium jump pack to get it going.



5. Alternator Test:

Measured the voltage:

13.8V at idle.

14V at 3000rpm.


Checked the alternator output with a Fluke DC clamp meter:

It was charging around 90A while the car was drawing about 45A.


The alternator seems to be working, and while 13.8V seems a bit low, I’ve seen people say this is normal for this model.



6. Current Draw Follow-Up:

Traced the 80mA draw to the cable that runs to the alternator and starter.

The cables to the engine fuse box and interior fuse box weren’t pulling any current when the car was locked for ~15 minutes.

7. SDD diagnostics

No outstanding or history dtcs.




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Where I’m At Now:

The car still drains the battery and refuses to start after as little as a day or two. I’m kind of out of ideas at this point. I’ve ordered a dual battery kit and plan to install a 60Ah battery in the boot for peace of mind, but I know this is more of a Band-Aid than a real fix.


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Looking for Advice:

Has anyone dealt with a similar issue?

Any idea why the alternator-starter cable would still draw 80mA when the car is locked?

Could the alternator voltage (13.8V at idle) be part of the problem?


Any help would be hugely appreciated! Thanks in advance! 2010 Vogue 4.4 TDI
2005 Subaru Outback H6 3.0
1991 Nissan Pulsar GTI-R AWD 2.0

I would guess the alternator diodes are on the way out hence the current drain and the alternator voltage not what it should be. No doubt someone will correct me.

Agree - voltage on the low side for a smart AGM battery charging system. If you turn on all possible electrical systems it should be showing 14.7 v max when running properly. 2012 TDV8 Vogue (L322)

Voltage was 12.73 before bed last night, 12.68 this morning.

Car was locked with hood open and button pulled up so I could access the battery without unlocking.

Going to double check the current draw direction again when I can get the clamp meter later on. 2010 Vogue 4.4 TDI
2005 Subaru Outback H6 3.0
1991 Nissan Pulsar GTI-R AWD 2.0

Draw should be <20mA when everything is off

80mA is too high

Agree with others about charging voltage being low
Should be 14.7v plus / minus 0.3v depending on battery condition and temp

Called around today to find an alternator LR022528 (DAN1110) and they are going for about $650-1100Aud depending on how quick I need it, is there any more testing I can do to confirm this is the culprit before I pull the trigger?
Also looks like a bit of a hassle of a job, not the worst but would prefer not to go down that path 😂 2010 Vogue 4.4 TDI
2005 Subaru Outback H6 3.0
1991 Nissan Pulsar GTI-R AWD 2.0

What's the charging voltage with the engine running and all electrical systems turned on. 2012 TDV8 Vogue (L322)

Is it not possible to have a local auto electrician check the alternator and possibly even change the diodes. A lot cheaper than a new fitted alternator.

I’m having the same issue with my L322 alternator draining the battery.
Try disconnecting the cable from battery to alternator and if the battery holds a charge overnight it’s likely the alternator is shorted to ground.
With the + cable disconnected at the boost post test continuity of the + cable to chassis ground.
My truck is an HSE so the alternator wiring may not be the same.

Tested continuity between the alternator positive and its body, nothing...

Also took it on a proper drive to monitor voltage as I had someone to help me, with all of the power turned on, seat heaters, defrost, high beams, etc...

As I turned on the loads voltages dropped briefly to around 12.8 then quickly recovered to 14.0-14.1v.
Turning off all the loads Voltage was between 18.913.8-14.2v while driving and stationary.



Car has sat for two days since its last full charge (from the wall) and had one good start yesterday to make some space in the garage, sat for >30 min then clicked and failed to start, after a minute it kicked over successfully.

Today car started for the test drive with no problems and battery voltages have been fairly stable.

Kinda making me doubt the new starter at this point. 2010 Vogue 4.4 TDI
2005 Subaru Outback H6 3.0
1991 Nissan Pulsar GTI-R AWD 2.0

Last edited by lofty248 on 26th Nov 2024 11:31am. Edited 2 times in total

18.9v is not good at all suggesting voltage regulator in the alternator not working properly. This will damage the battery. Under full load while the engine is running 14.7 should be as high as it goes. 2012 TDV8 Vogue (L322)

That was a mistype! Meant to be 13.8, if I saw it hit 18.9 that thing would be straight in the bin... 2010 Vogue 4.4 TDI
2005 Subaru Outback H6 3.0
1991 Nissan Pulsar GTI-R AWD 2.0

Is your ignition switch working properly?

My 2012 WM twice drained its battery and in each case it was a software fault. The first time the battery (about a year old) ceased to be able to hold charge and was replaced. So consider getting a diagnostic test done/having the software rebooted, and checking whether the battery can still hold charge after being discharged. Apparently the battery needs to be fully charged before it can be tested for this.

That car also had the "click when starter pressed" intermittent non-starting, cured by fitting new starter motor (you have done this already, the starter button is known to go wrong too, maybe something around the starter as you have been investigating too). Only Range Rovers since 1988

f you press the starter and it CLICKS, what is the voltage in the battery? Is it under 12.5 volts? Can a ground cable also be loose or corroded? Did you have the problem before replacing the starter? What if you disconnect the charged battery from the car and then wait four days, does it start immediately when you reconnect the battery? I also had the problem in my many Range Rovers, it was the ground cable.... L405 SDV8 2017 + Lancia Flavia Coupe 1964 + RRS L494 3.0 SDV6 + C220CDI Convertible 2021