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MG latches for the LH, passenger door are no good as they only have one microswitch and the P38 needs 2. That would explain why the plug is different, less switches needing less wires. You could fit a LHD LH MG latch though as that will have a full set of switches.

Later (mid 99 onwards) P38 latches have a single 8 way plug with only 7 ways used.

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That makes sense, thanks.

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If you've got an earlier 1995, then these had issues (which later BECM firmwares fixed) with spurious RF causing the BECM to freak out and constantly lock the doors.

Later BECM firmwares obviously has something written into them, so that if it got an overload of RF then it would only relock the doors a couple of times I think, before it would then not try to drive the motors again.

I saw it a LOT on earlier vehicles where the front door latches would burn the motors out, but for whatever reason (maybe because they were driven by the BECM directly, not the outstation like the front doors) the rear ones never suffered this fate.

The bad news for you is that you need 2 new front door latches to fix it. From what you have described, all the latch microswitches are working as they should - the key is unlocking/locking the vehicle and setting/turning off the alarm/immobiliser. The drivers loor lock will always lock/unlock with the key in the door as it's mechanical. The microswitch is obviously triggering as the BECM sees the change in state and locks/unlocks the rear doors, but the passenger door doesn't do anything as the motor is burnt out. Likewise, when you lock/unlock the passenger door with the button in the door card, it is mechanically locking/unlocking that door, and triggering the central locking switch. The BECM sees this and signals to lock/unlock the other doors - but since the drivers door motor is burnt out, it won't do anything.

The best overall fix for you would be replacing the 2 front door latches, and an upgraded RF receiver (I'd say one of our fob filters as they're cheaper, but we don't have any at the moment - maybe in a few weeks if we can actually order some parts that have been unobtainable the last couple of years!).

Just be aware, that if you replace the front door locks, and not the receiver, then it's entirely possible if the BECM gets flooded with RF, then it could trigger the doors to lock and this will then cause the motors to burn out again. I've seen it before when someone replaced both latches, only to have them cooked again in a couple of months. With the updated receiver/RF filter this filters out EVERYTHING other than a P38 key fob, so the BECM is kept blissfully unaware of any other RF, and thus will only drive the door lock motors when it has received a valid lock/unlock code (or the key is turned in the drivers door or one of the front locking buttons is pressed.

As Gilbert says, some of the earlier MG latches work in a P38 - though some have an extra wire as I think they supplied a signal when the latch was locked aswell as when it was unlocked - from what I can remember anyway.

I think I have a RHD/RHF (drivers) latch in the early style (with the connectors moulded into the latch body) here which I refurbished aged ago for someone. I can't remember if I have passenger side too.... The later (version 2) latches would also work in your vehicle as the main 6 way connector is the same - but you would need to cut/ connect the black ground wire as the connector for that is different from V1 to V2 of the latch. The later V3 latches (whilst physically/mechanically the same) have a single connector on them, which is only compatible with the post '99 vehicles.

Hope this helps.
Marty

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Bloody hell, you're alive!!!! I've been asked by a number of people if you were still about and I've had to tell them that you (and Nick) had gone AWOL. Welcome back mate, are you in the UK or did you just manage to find a bit of spare time to pop up on here?

Martyuk wrote:

As Gilbert says, some of the earlier MG latches work in a P38 - though some have an extra wire as I think they supplied a signal when the latch was locked aswell as when it was unlocked - from what I can remember anyway.

The difference with the MG latches is that instead of having 6+1 connectors, they have 6+2. The 2 way connector has the Black ground wire in it the same as the single connector on the P38 latch and the other wire is simply the grey from the latch that appears in two places, once in the 6 way and again in the 2 way so can be ignored if using it in a P38. The 6+1 latch and the later ones (99 MY onwards) that have the 8 way (but with only 7 ways used) are the same latch except for the connector, even the wire colours are the same, so an MG latch can be used in a later car if the 2 plugs are chopped off and the later plug fitted instead.

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Gilbertd wrote:

Bloody hell, you're alive!!!! I've been asked by a number of people if you were still about and I've had to tell them that you (and Nick) had gone AWOL. Welcome back mate, are you in the UK or did you just manage to find a bit of spare time to pop up on here?

Yes, I am alive - just been keeping stupidly busy over the last 18 months, and pretty much had no time for anything RR based - not even on my own ones where there are plenty of projects that I want to work on!

Currently back in the UK, yes - but only for a couple more weeks as I'm sorting through my stuff and packing it to ship to NZ. I am hoping that once all of my stuff arrives there, I can get back into some P38 projects. Though I managed to catch up with Nick the other day (He's been stupidly busy too, and I haven't really been in touch with him much in the past year or so either) and we are hoping to be able to get some things looked at (like some more RF filters made now I've actually been able to source some parts) whilst I'm here. Though going forward I might look at doing a re-design of the RF filter, so we don't need to do as much assembly on it, to make it easier for me to be able to look after making them in NZ and shipping them from there, either directly, or to Nick/someone in UK who can then distribute them. Things like that will need a bit more thought once I've managed to get my stuff safely packed up and shipped overseas though.

In the meantime, I will attempt to jump on here a bit around my packing/sorting etc

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Thanks Marty, very useful - interested if you do have any latches.

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I will have a look tomorrow and see if I have latches to suit the '95s. I am pretty sure I have a drivers side one, and if I don't have a passenger side one, then I'm pretty sure I'll have the bits to make one.

I also should have RF filters available again later this week as I have been able to finally source some of the microcontrollers which have been unobtainable for the last couple of years...

I'll drop you a message on here or PM me your email address and I will email you once I've looked through my parts here. (It's a bit of a jumble as I'm still sorting what I'm going to take overseas and what will stay here! But should get time tomorrow to have a proper look for you)

Cheers,
Marty

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Gonna miss you in the UK mate!

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Morat wrote:

Gonna miss you in the UK mate!

I'll miss being here (at times!) I definitely will be back again for visits (especially until I decide to sell the house). I'm hoping that I'll end up having a bit more spare time to be able to actually get back on the forums - and potentially work on some more parts - even if the shipping is a bit more expensive from NZ. I have a few more ideas on P38 projects that I want to do, including a 'drop in' replacement switch pack for P38 door latches... I've prototyped a few up whilst I'm here (using some 3D printed parts) and going to include a bunch of door latch parts in my boxes of stuff to go to NZ, so I can potentially do some rebuilds of them, and test out my new switch blocks.

I'm also going to have my P38 BECM tester and diagnostics with me over there, so hopefully some BECM services will be back on board again too - shipping a logic board isn't the end of the world, so fingers crossed the distance doesn't prove too much...

My partner has never been to the UK, and I'm hoping she can come over with me next year (as I'll have to come back to sort the workshop out/potentially shipping the P38 to NZ) - so hopefully there will be some time for showing her around the country - so will have to come up your way to catch up!

How's the Duchess going?

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Philip wrote:

Thanks Marty, very useful - interested if you do have any latches.

I had a look today as I was sorting through a bunch of my P38 stuff... I have a drivers door latch with the moulded connectors already assembled and available. I don't have a passenger one assembled, but I have one here which I will try to strip/rebuild tomorrow so it's also available.

Fingers crossed my P38 passes the MOT tomorrow, so I can get out and about rather than being at home a relying on deliveries... and I can get some epoxy to finish the RF Filters aswell...

Cheers,
Marty

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A thank you to Martyuk for getting the latches and filter to me next-day when he had far more important things to be doing.

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Marty, thanks from me as well. Second filter arrived last week, so now my project car sleeps properly & battery no discharging anymore.

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No worries! Hope all is well with your respective P38s still!

Back in NZ now and busy with work again, and preparing to battle with customs to get my stuff here without having to pay stops amounts of tax because according to the removals firm, my travel movements over COVID make me ineligible for duty free import of my personal possessions... And have noticed useless for any kind of help (despite paying them nearly 4k to move my stuff!).... No advice or compassion either just "it's your responsibility to know the regulations"... Again despite them shifting things around the world every day for people and me never having shipped stuff off this magnitude to the other side of the world before... Rant over haha

I'll try to check in on here on some of my days off 😀

Cheers,
Marty