battery drain

[jeff]

I have a W reg 4.6 vogue , only just bought the p38 , and the battery will only last a couple of days , and then is totally flat ,

could this be a bad battery or something else , when locked there is a red led flashing all the time?

thanks

 

[Datatek]

These cars need a good battery something like an Alphaline C31 135AH 1000CCA. Battery drain is a common problem, usually caused by the RF receiver keeping the BECM awake. Do a site search, hundreds of threads on this.
Red light flashing on the dash is normal when locked, read your owners manual for more info.

 

[Don1]

Hi Jeff,
Spurious WiFi signals can be picked up by the RF reciever and stop the Becm
from going into sleep mode. You can check this by locking the car and watching the red LED dot next to the gear leaver. This LED is lit dimly until the BECM goes into sleep mode after about 60 secs I think and then goes off. If this LED remains dimly lit this indicates the Becm hasn't gone into sleep mode and overnight will drain the battery.
Note the LED is very dim so this is best done in the dark.
Of course there are many things that can cause battery drain.

If you add your location someone near may be able to help you out.

 

[dogsbody]

Hi Jeff,
Spurious WiFi signals can be picked up by the RF reciever and stop the Becm
from going into sleep mode. You can check this by locking the car and watching the red LED dot next to the gear leaver. This LED is lit dimly until the BECM goes into sleep mode after about 60 secs I think and then goes off. If this LED remains dimly lit this indicates the Becm hasn't gone into sleep mode and overnight will drain the battery.
Note the LED is very dim so this is best done in the dark.
Of course there are many things that can cause battery drain.

Even if the BECM goes to sleep it can be woken later.
Try disconnecting the window aerial from it. It doesn't totally cure the issue but radically reduces it's effective range so, hopefully, stops it picking up whatever is turning the BECM on.
The RF receiver is behind the trim panel on the offside of the boot space.
The trim is held by two plastic plugs and a screw hidden by the back seat.
The aerial lead is the single blue cable heading up into the window.
Do not disconnect anything else.

 

[marcinbrighton]

You'll probably end up buying one of these:

RF Radio Receiver YWY500170 Island 4x4 - Specialists in Land Rover and Range Rover Parts and accessories for all models. UK and worldwide mail order..

Expensive (ish) but a lot less hassle when it actually starts when you want it to!! I had a temporary fix on mine by putting a switch on the +ve feed into the existing receiver (suggested on rr.net). Worked fine, but on advice from Datatek re burnt out locks (do a search) I bit the bullet and bought the one on the link. No problems since then.

Couple of checks you can do to establish if it is actually that (in addition to the suggestion on the blue wire from Dogsbody), if you take the receiver apart, the latest version (the one in the link) should have two circuit boards (one sticking up from the other). The earlier versions don't. They are colour coded with sticky dots on the outside, but those can't necessarily be trusted cheers to unscrupulous fleabayers!!

If you can do without the rangie for a few days, unplug the white multiplug from the receiver and leave it. If it doesn't go flat, bob's your mother's brother.

The car won't start though if its disconnected - will give 'engine disabled' on the dash. Mine did this lots when I had the switch on there and I forgot to turn it on when I went to start it!

Hope that helps

 

[jeff]

Thanks for the reply's

Done a search on the disconnecting the blue wire,
If I do this will my locks burn out? Will it effect anything else?

So if I disconnect white plug to receiver , and leave for a few days and battery doesn't go flat , all I need to get is the new updated receiver and fit?

Thanks

 

[dogsbody]

Thanks for the reply's

Done a search on the disconnecting the blue wire,
If I do this will my locks burn out? Will it effect anything else?
Disconnecting the aerial stops the spurious signals from firing the lock circuit and may save your door locks.

So if I disconnect white plug to receiver , and leave for a few days and battery doesn't go flat , all I need to get is the new updated receiver and fit?
Give it a little longer. This might be part of your problem but you may need a week or two to prove that it's the only one. Or it could be something from a neighbour's house and if they're on holiday for a fortnight . . .

Thanks

Good luck

 

[jeff]

Good luck

don't really have neighbor's close enough, but have WiFi and gate opening remote , could these cause it?,

also with the blue wire disconnected , will the key fob/remote , still work , what negatives is there with doing this ?

thanks

 

[NikTheGeek]

You can check this by locking the car and watching the red LED dot next to the gear leaver. This LED is lit dimly until the BECM goes into sleep mode after about 60 secs I think and then goes off. If this LED remains dimly lit this indicates the Becm hasn't gone into sleep mode and overnight will drain the battery.
Note the LED is very dim so this is best done in the dark.

What LED near the gear leaver? I don't have one (2002 DHSE) just been out and checked in the pitch black. Deffo no LED??? Do you mean the gear selector LED?

BTW Jeff, you can try a cheap fix that works on my second generation receiver: wrap it in foil and put snap-on ferrites on the power leads. I have no problems touch wood. It will prevent RF being picked up on the circuit board of the receiver as it shields it. The ferrite stops RF being picked up via the vehicles wiring. It's a £2 fix if it works and only £2 wasted if it doesn't. Never tried it on a first generation receiver so results may vary etc etc

Nik

 

[dogsbody]

don't really have neighbor's close enough, but have WiFi and gate opening remote , could these cause it?,
Depending on your receiver, yes.

also with the blue wire disconnected , will the key fob/remote , still work ,
The fob should still work

what negatives is there with doing this ?
You'll have to be a bit closer to that corner of the car when you operate it.

thanks

my pleasure

 

[Don1]

What LED near the gear leaver? I don't have one (2002 DHSE) just been out and checked in the pitch black. Deffo no LED??? Do you mean the gear selector LED?

BTW Jeff, you can try a cheap fix that works on my second generation receiver: wrap it in foil and put snap-on ferrites on the power leads. I have no problems touch wood. It will prevent RF being picked up on the circuit board of the receiver as it shields it. The ferrite stops RF being picked up via the vehicles wiring. It's a £2 fix if it works and only £2 wasted if it doesn't. Never tried it on a first generation receiver so results may vary etc etc

Nik

Hi Nik,

Just checked on mine (2000 4.6 Thor) and it's in line with the gear selecter in park position.
Maybe it's only on auto's, I never thought about manuals. It is very dim and takes some spotting.

 

[Don1]

don't really have neighbor's close enough, but have WiFi and gate opening remote , could these cause it?,

also with the blue wire disconnected , will the key fob/remote , still work , what negatives is there with doing this ?

thanks

Hi Jeff,

I have a clamp amp meter and when I checked mine I found it would go into sleep mode then wake up again after a few seconds. I have read before that wireless (electricity) energy monitors have a range of about 30 metres and cause this issue.

I have had the blue wire removed from the RF receiver for a while now. When I unlock the car I have to start it within a minuit or so or it won;t turn over, I just have to lock it and unlock again to start it. I do have to use the remote close to the rear window as well.

Don't forget there are many other causes of battery drain but this issue is very common
if you don't have the latest revision RF receiver.

 

[jeff]

just been and had a look at mine ,

i have no led near the gear selecta , mine is a 2000 4.6 thor ,

i will give the above ago ,

also I seem to hear a humming noise inside the car?

 

[Saint.V8]

There should be a little red light next to the gear selection number .... this little lamp remains on while the BeCM is awake and goes out after about 3 minutes of engine off and car locked....

Little Light...

 

[NikTheGeek]

There should be a little red light next to the gear selection number .... this little lamp remains on while the BeCM is awake and goes out after about 3 minutes of engine off and car locked....

Ah, I was checking an unlocked, but already parked car so the engine had been off for a couple of hours. I'll try again with a running, then turned off, then locked car...

tnx

Nik

 

[Datatek]

What LED near the gear leaver? I don't have one (2002 DHSE) just been out and checked in the pitch black. Deffo no LED??? Do you mean the gear selector LED?

BTW Jeff, you can try a cheap fix that works on my second generation receiver: wrap it in foil and put snap-on ferrites on the power leads. I have no problems touch wood. It will prevent RF being picked up on the circuit board of the receiver as it shields it. The ferrite stops RF being picked up via the vehicles wiring. It's a £2 fix if it works and only £2 wasted if it doesn't. Never tried it on a first generation receiver so results may vary etc etc

Nik

Your silver foil and ferrites mod will not stop the receiver burning your locks I'm afraid.

 

[NikTheGeek]

Your silver foil and ferrites mod will not stop the receiver burning your locks I'm afraid.

Ah, but surely it only does that because it is detecting RF and activating? Let's assume it receives nothing at all (because it's put in a sealed lead box and buried under 10 foot of earth for example) then it's not going to burn your locks then. Or is it? Is there something else I'm missing? Is something else other than RF coming in to play?

Nik

 

[Datatek]

Ah, but surely it only does that because it is detecting RF and activating? Let's assume it receives nothing at all (because it's put in a sealed lead box and buried under 10 foot of earth for example) then it's not going to burn your locks then. Or is it? Is there something else I'm missing? Is something else other than RF coming in to play?

Nik

You are missing the fact that there are 2 separate issues. One is the RF interferance, the other is a component failure in the early receivers that causes the output to oscillate burning your locks It's been well reported.

 

[NikTheGeek]

You are missing the fact that there are 2 separate issues. One is the RF interferance, the other is a component failure in the early receivers that causes the output to oscillate burning your locks It's been well reported.

Ah, ok. Sorry. I get it now. I'll shut up

 

[jeff]

right i have found the little becm light now , and it goes out after a couple of minutes and doesn't wake up , (this is after ive disconnected the blue wire) i haven't tried it with the blue wire connected yet,

this is my receiver in the car , can anyone tell what version it is?

also sat in car locked for a few minutes and i can hear a high pitch noise coming from the center interior light area , surely this noise must be draining power , does any one know what fuse goes to this unit or why it makes this noise?

thanks again