PS, welcome to the forum

Depends what system it had originally and what year. There were 4 different stereo systems fitted over the years. Earlier cars had a Clarion head unit and could have had the Low Line system, with a bass speaker in each door and a tweeter at the top of the front doors, a Mid Line system with bass and midrange speakers in the doors and tweeters at the top of the front doors, or the High Line system with the same speakers as the Mid Line but with amps in each door, a sub in the boot and steering wheel control buttons. Later cars had an Alpine head unit and the premium system had a DSP amp in the boot which is notoriously unreliable, fails regularly and will cost a fortune to replace.

If you have the Low or Mid line system, the connectors at the head unit are standard DIN plugs so any aftermarket head unit should just plug straight in. If you have the High line with door amps you either need to make up some attenuators or bypass the amps and fit crossovers instead.

Keycode Lockout comes up if the alarm has been triggered, the battery disconnected (or gone flat or you got the EKA wrong more than 3 times) and is reconnected. As you have found, you just need to be patient.

The sump isn't the same. Pre-99 GEMS has a pressed steel sump but a later Thor has a cast alloy one (which incorporates the flywheel cover rather than it being separate) which probably explains the difference. I've never seen anyone use a torque wrench on a sump plug, most people just do it up tight......

It's touch up paint for the car but slobbered on good and thick so it is opaque. I used it because I figured it wouldn't look so obvious and it happened to be sitting on the shelf in the garage. If it can be put on thick enough to stock the light coming through, silver paint would probably be the least noticeable. If you follow the mouldings on the light units and shine the headlights on a wall, you'll see the dip pattern is flat if you got it right.

As I do more long distance driving on the wrong side of the road than over here, I've masked my lights to give a flat cut off on dip. I've painted mine as tape gets pulled off by the headlamp wipers but tape will work just as well if you put it in the correct place.

RH lamp

LH lamp

If you look, you'll see the lens has the sections marked that need to be masked.

On a P38 you can take the rear door off for access and cut through the loop the door latch catches on. That at least allows you to open the door and get the door card off to get at it. No idea if you can do the same on an L322 though.

No problem with using a dead fob as a manual key, not until you wear out the keyswitch in the latch anyway. That is the problem with the cheap fob cases, they don't hold the pcb securely so it can move inside the case.

Usually one door not locking means the CDL switch has failed so it doesn't try to lock it as it thinks it is already locked. However, if pushing the sill locking button down locks the other doors, that would suggest it is working. I suppose the only possibility is that it is failing so manually pushing the sill button down moves it further, just enough for it to operate?

As Rob assumes I know every little item on the P38 I thought I should check and confirm. I had a feeling the buttons weren't the same as the ones in the window switchpack so had a look at the HEVAC ribbon strip repair document on Marty's website (http://p38webshop.co.uk/index.php?route=product/category&path=71). I had a feeling the switches behind the buttons were the same as on a TV remote and the picture on page 5 confirms this. Take it apart as for as that picture, then lift up the membrane, clean the pads on the bottom of the membrane and the tracks on the circuit board that the pads bear against with alcohol and put it back together.

mad-as wrote:

Hi Chasman, just for interest i have heard off this RF interference issues being caused by other electronic gadgets , eg weather stations and wireless security window locks etc. the problem seems to be when the battery's go flat and the units send out a low battery signal , it's these signals that interfere with cars

From many years of experience of tracing these sources, you are absolutely correct. Most things just stop working when a battery goes flat but Murphy's Law says that a device that has been designed to operate every 15 or 30 minutes, or only on a change of state, operate all the time. Ones that I found over the years were window sensors on burglar alarms (which also get offended when a spider takes up residence inside), oil tank level gauges and weather stations. Then there are inadvertent sources, remote controls jammed down the side of a sofa with a button pressed in, kids toys left switched on, wireless doorbells with the button stuck in and so on.

Wi-Fi and radio transmitter sites can cause a problem but not a battery drain, just a fob that won't work. When a radio receiver, no matter what type, is near to a high powered RF source, it suffers desensitisation so can no longer detect the wanted signal. Think of it like trying to listen to someone talking to you when you've got a lot of loud noise around you. This is when you get the situation where you park somewhere and can't lock or unlock the car with the remote. Putting the remote next to the receive aerial on the window will usually work as it is the R|F equivalent to shouting in someone's ear.

If it was unlocked it should have started unless passive immobilisation is still enabled as it needs to receive an unlock code to reset the immobiliser. That will kick in if the car is unlocked but not started within 30 seconds. Ordinarily it will receive an unlock code when the key is put in the ignition, the coil around the lock causes the fob to transmit without you noticing (unless you happen to look at the LED on the fob as you put the key in, you'll see it flash).

No need to match anything, a receiver is a receiver and you can swap them at will. They all do the same job, just some versions better than others.

The system operates on nominally 433.98 MHz and the Gen 1 receiver was appalling, it would respond to any signal between about 425 and 440 and wake up the BeCM. I say nominally as external influences will affect the precise operating frequency so the receiver needs to be wideband to a certain degree. Just not as wide as that of the Gen 1..... The Gen 2 had much better selectivity so would only respond to signals much closer to the operating frequency but will still wake the BeCM upon receipt of a signal from any other licence free short range device in that band (433.05 -434.79 MHz). The Gen 3 receiver performance is pretty much the same but the difference is that it doesn't wake the BeCM until it sees a valid P38 code.

Marty's RF filter does the same thing, the receiver, irrespective of which one, receives a signal, instead of passing it directly to the BeCM it is passed to the filter which checks to see if it is a valid P38 code. If it isn't, it rejects it but if it is the code is then passed through to wake up the BeCM. All P38 codes have the same pre-amble before sending the individual code for the car so all will wake up the BeCM but only the correct, matching, code will turn off the alarm and immobiliser and allow the engine to be started.

davew wrote:

Well at least Mr. Griffith would be impressed you remembered the Inverse-Squared Law: Pity he was not able to explain that to LR 30 years ago as their RF Engineers were so bad.....

It was BMW at the time and the 7 series of similar vintage was just the same. The receivers were made for them by Siemens but made to a price. When I sent a report as to why they suffered it was passed through various departments before ending up at Siemens who's reply was "When you are only paying 0.09 Euro per receiver, you can't expect quality"

Yes, we can't see your Sooz pic

You can now, I've edited the post.

If you disconnect the blue antenna wire from the receiver, you'll need to be closer for the fob to work but it will reduce the interfering signal it it receiving.

I have the same, something my next door neighbour has will keep waking up the Ascot but not mine as the Ascot is a 96 with the early receiver, mine is a 98 but with one of Marty's filters on it. If I park mine nearest the neighbours house with the Ascot the other side of it, not a problem with either, if the Ascot is nearest the neighbours then the BeCM is constantly woken up.

davew wrote:

Richard, yes, and that's what I thought too... and that the Timer Relay was only supposed to operate for 20 seconds every 6 hours... under BeCM control...

No it isn't, the relay contains the timer (probably by a 555 timer chip or similar) and isn't controlled by anything else, it just wakes up. If you look at the diagram, it has permanent power on one side and ground on the other.

Chasman wrote:

Okay, removing the EAS delay relay stopped the cycling. Thank you!

That's odd, it's only supposed to wake up every 6 hours?

There shouldn't be. Radio has a permanent supply to keep the memorised stations, clock, alarm and that is about it once the BeCM has gone to sleep. That happens 2 minutes after no inputs to trigger it. Easy check you can do is to sit in the car at night. While the BeCM is awake, the red LED next to the gear lever position will be glowing very dimly while it is awake and will go out once it is sleeping. So if you get into the car, close the door, sit there watching the LED and you should see it go out after 2 minutes. If it is the BeCM being awoken by something, you will see it come back on again at the time the current draw would go up again. You can easily wake it at will if you have a keyfob for your other P38 by pressing a button on that. With a Gen 1 or 2 RF receiver, it will see the transmission from the other fob and wake the BeCM in anticipation of receiving a valid code, (which it won't get as the fob is for the wrong car) and that will start the 2 minute timeout again.

The SID gives a list of all the things that will trigger it and wake it up (or prevent it sleeping in the first place) so you can go through the flowchart and isolate which input is triggering it if it is being woken by something.

Yes it does work. A friend does mobile AC recharging and he has suggested it to a few customers that were in a similar situation to you and it has cured very small leaks. In fact, there's a can of it in Dina's Merc which had a very small leak from the evaporator and I think Merc started there and built the rest of the car around it making replacing it more than just a PITA. That was losing charge after a couple of months so if it can seal that it should do yours without a problem. Follow the instructions to the letter though or you'll end up getting covered in it.

Usual place for leaks on a P38 is the top corner of the condenser but with a leak as slow as yours, even putting tracer gas in and using an electronic sniffer it would be difficult to detect.

In my previous life before retirement, my work involved tracing this sort of thing. I would say that the BeCM is sleeping so you should have around 0.03A (30mA) but when it is awake it will rise to just under an Amp. For it to cycle it could well be something transmitting every 4-5 minutes so the BeCM sleeps, is then woken up, it waits then goes to sleep again and the cycle starts again. Favourite source at that kind of interval, would be the outdoor unit for a wireless weather station.

But, as Dave has said, the BeCM SID has a list of things that can wake the BeCM up and a flowchart to follow to identify what is the cause. I posted a link to it here https://rangerovers.pub/topic/3311-reconnecting-battery-alarm?page=1#pid40747

Open the door, open the bonnet, close the door and then reconnect the battery. As long as the status when the battery is reconnected (doors open or closed, doors locked or unlocked, etc) is the same as when it was disconnected, you shouldn't have a problem.

If the car is going to be left for any length of time, open the bonnet, then close and lock all the doors, disconnect the battery and close the bonnet. When you want to reconnect, open the drivers door (which, with the battery disconnected will be the only one that will unlock), open the bonnet, close the door and lock it, then reconnect the battery.

How much current drain do you have? Do you have the BeCM SID with the current drain diagnostic flowchart, if not, it's attached.
enter link description here

Info you need is from page 10 onwards.