Disconnecting battery

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Andyp38

Active Member
Posts
150
Location
Bridport,Dorset..
Well i'm off on holiday for a few weeks soon,and i'm going to be putting my 4.6 p38 in a lock up whilst away.

Anyway i want to disconnect the battery,as i dont trust it to stay charged in that time :doh:

So whats the best procedure for disconnecting?
Just take the leads off or set the alarm then disconnect.
Is there a specific factory procedure?
I hope the eka code i got from landrover is the right one :eek:

Yes ive tried the search button,and no i dont have the manual in the house. And its to dark to go to the garage and find it :D
 
Got no power source to my lock up unfortunately :(

I'm hoping that with the key out the ignition,there cant be any power spikes to damage any ecu's when disconnecting..

Must be better than leaving the battery, to gradually run flat !
 
dont disconect with the alarm armed it will think its been tamperd with and trigger a eka lockout
best leave it coneccted and when you come back take a spare battery and jump leads just it case.but it shoulden drain flat over just a few weeks if everything works ok
 
Have you got a window /light in to the lock up?
I use a small solar panel resting on the dash, attach leads to the battery with its thin wires so the bonnet and door can still shut. works a treat, with enough trickle charge even on a winters day.
 
dont disconect with the alarm armed it will think its been tamperd with and trigger a eka lockout
best leave it coneccted and when you come back take a spare battery and jump leads just it case.but it shoulden drain flat over just a few weeks if everything works ok

Not a good idea as when the battery voltage drops, the ECU's go crazy, better just hook the neg off and it should be OK, but make sure you charge the battery before re-connecting. Low volts are the cause of many problems.:)
 
Not a good idea as when the battery voltage drops, the ECU's go crazy, better just hook the neg off and it should be OK, but make sure you charge the battery before re-connecting. Low volts are the cause of many problems.:)
which solar panel/regulator do you use when leaving your motor?Ive used a 1.5 watt panel which will not keep the battery charged but will prevent total loss of power ie you dont have to reset windows,sunroof etc.I could do with something with a bit more power to keep battery fully charged.Im back to the Canaries in a couple of weeks for a month so any help would be appreciated.regards
 
I do have a solar panel wired to the battery,(through a regulator) but its fixed into the back window and its pitch black in my lockup :doh:

Think i will disconnect it like rewmer says,then when i come back i will add my jump pack to it as well for extra boost !

Thanks for everyones advice :5bcheers2:
 
Sorry to resurrect an old thread but I wondered how the disconnect went.

My P38 (4.6 Thor) gets left in my office underground car park for a few weeks at a time during the warmer months. No power is available for a trickle charge or light for a solar charge. It has the remote antenna disconnected - and I imagine doesn't see too much radio interference down there - except of course other car remotes. Charging is good (voltage correct and a clamp meter showing many tens of amps from the alternator) and battery stress tests well (and is quite new).

When I return to it after maybe 2-3 weeks, the battery has always discharged too much to start (even if it started with a full charge - I can charge it when it is at home). It usually has enough juice not to cause any errors and to unlock etc., but needs a jump start - which is a pain!

It has entirely standard electrics with no aftermarket goodies that might be draining the battery and obviously has a bit of history because previous owner receipts show the BECM sleep test having been done (and passed).

So I'd quite like to leave it disconnected to save the battery from damage and for an easier re-start. I could live with re-syncing the windows etc. However, I don't particularly want to get locked out or immobilised!

I believe the earlier cars have this 17 second thing between ignition on/off and disconnect, but the later cars are different. I have the EKA code and have confirmed it works by re-syncing a key a while back, but don't really want to experiment, even with RAVE to hand, unless I have to. Can anyone confirm from experience, how best to routinely disconnect and reconnect the battery on a late P38 petrol?
 
Sorry to resurrect an old thread but I wondered how the disconnect went.

My P38 (4.6 Thor) gets left in my office underground car park for a few weeks at a time during the warmer months. No power is available for a trickle charge or light for a solar charge. It has the remote antenna disconnected - and I imagine doesn't see too much radio interference down there - except of course other car remotes. Charging is good (voltage correct and a clamp meter showing many tens of amps from the alternator) and battery stress tests well (and is quite new).

When I return to it after maybe 2-3 weeks, the battery has always discharged too much to start (even if it started with a full charge - I can charge it when it is at home). It usually has enough juice not to cause any errors and to unlock etc., but needs a jump start - which is a pain!

It has entirely standard electrics with no aftermarket goodies that might be draining the battery and obviously has a bit of history because previous owner receipts show the BECM sleep test having been done (and passed).

So I'd quite like to leave it disconnected to save the battery from damage and for an easier re-start. I could live with re-syncing the windows etc. However, I don't particularly want to get locked out or immobilised!

I believe the earlier cars have this 17 second thing between ignition on/off and disconnect, but the later cars are different. I have the EKA code and have confirmed it works by re-syncing a key a while back, but don't really want to experiment, even with RAVE to hand, unless I have to. Can anyone confirm from experience, how best to routinely disconnect and reconnect the battery on a late P38 petrol?

I have a late 2000 diesel, I just disconnect the battery as with a normal car, never had a problem, but the alarm sounder is disconnected so the alarm will not sound.
 
The book says disconnect the battery within 17 seconds of switching off the ignition from position 2. ( from memory )

WHOA there !

if the car has built in sat nav DO NOT disconnect the battery until the sat nav processor in the luggage hold has powered down. IE the light on the unit has extinguished or it will wipe the flash memory on the drive unit.

There is no where i know of in the UK that can re-flash the memory anymore so it's a new drive from land rover or one from the used market. (currently about £200)

Lots of sat-nav drives have been killed in the way.
 
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WHOA there !

if the car has built in sat nav DO NOT disconnect the battery until the sat nav processor in the luggage hold has powered down. IE the light on the unit has extinguished or it will wipe the flash memory on the drive unit.

There is no where i know of in the UK that can re-flash the memory anymore so it's a new drive from land rover or one from the used market. (currently about £200)

Lots of sat-nav drives have been killed in the way.
There is a Dutch company that I'm told can re-flash them, but you are right, if you are unlucky enough to have the built in SatNav, you must wait for the LED to go out before disconnecting the battery, that totally contradicts the 17 second business.
 
No factory sat nav on this one (rather expensive, and by modern standards rubbish, aftermarket VDO equivalent was installed quite nicely into the official LR dash surround though).

Doesn't have the standard kit on the right side of the boot, but instead an enlarged DVD drive (hung into the spare wheel well on mine). It's closely related to the factory nav - any idea if this will object to a powerdown?
 
No factory sat nav on this one (rather expensive, and by modern standards rubbish, aftermarket VDO equivalent was installed quite nicely into the official LR dash surround though).

Doesn't have the standard kit on the right side of the boot, but instead an enlarged DVD drive (hung into the spare wheel well on mine). It's closely related to the factory nav - any idea if this will object to a powerdown?
No idea, but always best to let the system shut down before disconnecting the battery rather than take a chance.
 
OK, many thanks.

Looks like I might just try it when I have the luxury of not needing to actually go anywhere!

I'll wait for the LED on the Nav DVD unit to stop first though.
 
if you are unlucky enough to have the built in SatNav,

Lol. I find it quite good and reliable with a good database of local amenties (i have the 2010 Europe disc map). i have google maps on my phone and a plug in garmin with live traffic. it also has the offroad DF and compass which the garmin and google doesnt have. Though, in surrey i'm not in the wilderness that much (only when north of toddington services).

The built in unit picks the same route as the garmin. it's not the most modern system in the world but its simple enough that the wife can use it both on maps and turn by turn.
 
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