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I'd say the meter is faulty and over reading. There's no way a fully charged battery not connected to anything, not even an MF31-1000, will show over 14V. I've got MF31-1000s on both my P38s and an MF31-750 on a 4.3 litre boat, I'll check those later ad tell you what I find.
 

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I've been out and checked all 3 of mine with a calibrated Philips workshop multimeter. The one on my car, which was last used last night, read 12.68V, the one on the spare P38, which was last used about 2 weeks ago, read 12.29V and the one on the boat, which hasn't been used for a couple of months, read 12.24V. It may be that they are overcharged when supplied new so can be used immediately, but will settle to the correct voltage once they have been used.

Charging voltage will be high initially to put back what has been used to start the car, so you can see up to 14.4V but that will drop to around 12.5-12.8V once the battery is approaching fully charged. That is what the regulator in the alternator does, it regulates to supply the voltage required by the battery.
 
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How much drain have you got? Is the BeCM sleeping or being kept awake by something else? Don't forget that the BeCM will be drawing just under 1A while it is awake, but will sleep if all doors are closed and nothing else is switched on to wake it after 2 minutes. Easy enough to check at this time of year. Sit in the car in the dark, close the doors (no need to lock them) and look at the red LED next to the gear lever, it will be glowing very dimly. but after 2 minutes it will go out signifying that the BeCM is now sleeping. If it doesn't sleep, something else is keeping it awake. BeCM is fed via Maxi fuses 1, 4 and 5. These fuses are fed directly off the main input cable. Then there are also fuses 25, 27 to 35 and 38 to 44, which are all connected to the main power input. So, when you say you have removed fuses, have you removed all of the permanently powered ones?
 

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The remote for the garage door is obviously operating on 433 MHz (which most low power momentarily operated diveces do in Europe), so that will be triggering the BeCM to wait for a valid unlock or lock code from the fob receiver. Difference between the recommended 25mA and 30-40mA is negligible, it would still take about 4 months to fully discharge an MF31-1000. Additional draw may be down to an aftermarket stereo or any other permanently powered extras.

If you are in an area with high levels of RF, or lots of remote operated devices, they can keep waking the BeCM up. You can spend a fortune on a Gen 3 receiver, wait until Marty has more of his RF Filter boxes back in stock (see Range Rover P38 Parts Shop) or, in the meantime, disconnect the antenna (blue) wire from the receiver. This means you will need to be closer to the car to use the remote but will greatly lessen the affect of other nearby devices.
 

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Calcium batteries can withstand a higher charging voltage than older non-Calcium enriched lead acid batteries. Hence a very early P38 will have an alternator that is regulated to around 13.8V maximum to prevent the battery being boiled dry. With the introduction of Calcium enriched batteries, which can accept a higher charging voltage, the alternators were changed for ones with the higher voltage regulator, around 14.4V. The figures you are measuring sound perfectly OK.

Do you actually have a battery drain problem, finding the battery flat after the car has been left standing, or are you just concerned about the 40mA drain which you feel is excessive?
 

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From the BeCM System Information document:

BeCM activation and Sleep modes
The BeCM has two modes of operation, normal operation mode or ''activation mode", and a low quiescent current state or "sleep mode". The sleep mode is required to enable the vehicle to be left for extended periods of time without the vehicle's battery being discharged.
Transitions between the two states are controlled by the status of the BeCM activation inputs (see activation input table).
Sleep mode will be entered when all timers have timed out (i.e. courtesy lights are off) and all activation inputs have been inactive for two minutes.
Activation mode will be entered when any of the activation inputs changes state. The quiescent current during sleep mode is approximately 30mA when the vehicle is unlocked and approximately 40mA when the vehicle alarm is armed.


So what you are seeing is completely normal and correct. (do not believe ANYTHING you read on facebook, there is more disinformation than stuff that is true on there).

CD changer being stuck probably means it is drawing current all the time, try unplugging it and see what the drain drops to. Don't forget you need to wait 2 minutes for the BeCM to sleep.

Yes, anything from '96 model year will have a higher voltage alternator.

I'll ask again though, do you have a genuine battery drain problem? My spare car, with an MF31-1000, has been parked up for over 3 weeks now. Just went out to it and it fired up straight away. That is a '96 with the 14.4V set point regulator but the Gen 1 RF receiver. So unless you intend not using the car, why would you need a battery maintainer?
 

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See the FAQ sticky at the top of this forum. Owning a P38 and not having RAVE is a bit like having a mobile phone but living in an area with no service.

I posted the BeCM SID in your previous thread......
 
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