THE BUDDAH

THE BUDDAH

New Member
SO,

I now have another problem to report with my p38.
Though i love this car i have never had so many problems with a any other vehicle.

This time its electrical. I get battery drainage if they car stands for a few days.
Just happened to me on a brand new battery.

Where do i start?

Mike.
 
Rf reciever behind right hand trim panel in boot. Disconnect blue wire and see if helps. If so replace the unit
 
THE BUDDAH said:
Is that radio frequency receiver ?

At a guess......lol
Click to expand...

Sort of, it's the receiver for the key fob to unlock/lock the car. It picks up spurious signals from other transmitters and this keeps the BeCM awake, thus draining the battery.
How long have you had your P38 before this issue? My battery was gone within a week of my buying the car, but unplug it and it solves the problem - although the key becomes useful only at a distance of ~1 metre.
 
I assume that the battery will hold a charge and that you`ve tested itwith a multi-meter ? Brand new doesn`t seem to mean much these days (I bought a brand new battery from Halfords as the only place local to me open on a Sunday and it drained over a week or so as well, they had had a bad batch so they said.......), and RR`s do seem to be very sensitive to battery condition
 
Funny you say that,

This is the second replacement battery iv'e had from halfords.
I bought the original three years ago, took it back after a year then took that one back after two years. Glad i kept receipts.

Mike.
 
THE BUDDAH said:
will the central locking and key control still work?
Click to expand...

Yes, although the range becomes pathetic, what year is your P38? I suggest checking your battery with a multi-metre with the engine off (after fierce debate between Data and Wammers :p ) it should read just over 12.5V and then with the engine on ~14V from the alternator; just to check everything's working there.
As has been said, the P38 really hates losing power - you can get loads of phantom faults; I've seen gearbox, traction, abs and engine... they all cleared with a recharge but still not a good thing
 
Right,

First of all thanks you for help.

Just tested battery tester read 12 and 25.8 not which is volts. (car not running)
13.8 and 29.8 with car running.
 
Last edited:
THE BUDDAH said:
Right,

First of all thanks you for help.

Just tested battery tester read 12 and 25.8 not which is volts. (car not running)
13.8 and 29.8 with car running.
Click to expand...

The 13.8's good - that will charge. The 12 suggests the battery's discharged, but since that's your issue that's to be expected. What are 25.8 and 29.8? :p
 
Have for the RF problem stuff, if you have an auto box the red LED glows when the BECM is active, it should go out after about 30 seconds (guess where you will be when it gets dark !) Disconnecting the blue lead can work, but just have alook on the posts about burnt out door lock motors. Bite the bullet and get the latest spec RF box, it makes life a whole lot more simple. Loads of stuff in the forums.
 
TCubed said:
The 13.8's good - that will charge. The 12 suggests the battery's discharged, but since that's your issue that's to be expected. What are 25.8 and 29.8? :p
Click to expand...

Sorry, 13.8 volts with the engine running is insufficient to fully charge the battery, especially if you do a lot of short runs. Lack of charge will kill the battery over time. 14 volts is really the minimum required 14.2 to 14.8 would be better but LR in their wisdom seem to use a 14.2 volt regulator set point giving around 14 volts at the battery.
 
Datatek said:
Sorry, 13.8 volts with the engine running is insufficient to fully charge the battery, especially if you do a lot of short runs. Lack of charge will kill the battery over time. 14 volts is really the minimum required 14.2 to 14.8 would be better but LR in their wisdom seem to use a 14.2 volt regulator set point giving around 14 volts at the battery.
Click to expand...

ffs - dont start that agin :).
 
Datatek said:
Sorry, 13.8 volts with the engine running is insufficient to fully charge the battery, especially if you do a lot of short runs. Lack of charge will kill the battery over time. 14 volts is really the minimum required 14.2 to 14.8 would be better but LR in their wisdom seem to use a 14.2 volt regulator set point giving around 14 volts at the battery.
Click to expand...

For a fierce discussion about this :p I still can't see why anything above 12.8V wouldn't charge a 12V battery, but let's not start that again haha

http://www.landyzone.co.uk/lz/f10/battery-drain-diagnosis-183458.html
 
TCubed said:
The 13.8's good - that will charge. The 12 suggests the battery's discharged, but since that's your issue that's to be expected. What are 25.8 and 29.8? :p
Click to expand...

different setting results on my tester, one set of figures are amp and the other volts.

Mike.
 
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