It's official, my P38 is properly sulking. BECM now?

Hi All,

Apologies for the long post...

Not content with costing me a small fortune to get it through the MOT just so that I could move it when I moved house. Still not content that the lpg vapourizer appears to have developed a leaky diaphram and it won't run properly on petrol either, it now seems to have decided to really go for the top prize.

I went out to it yesterday (it's currently parked on someone else's drive as I'm in the midst of house moves), to find all of the door locks cycling open/closed on their own. A neighbour mentioned that the alarm had been going off for a couple of hours earlier. That's never happened before - I wasn't even sure it worked! I wasn't very popular.

Because of previous battery issues, it was on a maintenance charger so I pulled that and disconnected the battery which shut the locks up. Prior to this it was completely unresponsive to the remote.

Thinking the battery had finally kicked the bucket, I put a brand new one in.
Unfortunately on connecting the earth, the starter motor kicked in all on it's own so it was hurriedly disconnected again.

Last week, I went to use it and found the electrical system totally dead (no interior lights, nothing hence it being on a charger). When I connected jump leads, it seemed to immediately revive but went straight to Key Code Lockout so I put it on charge and left it for the night. I managed to sort the key code issues out the next day and thought all was good until yesterday.

I've spoken to Rick_the_Pick briefly and he's suggested I pull the becm and send it to him.

Can anyone think of anything else it might be before I do this? My problem is the house whose driveway it is on has been sold and completes in about 9 days so the Rangey has to be moved before then and I'm starting to panic a bit! If I could move it a couple of hundred yards under it's own power then that would give me another 6 weeks, but it's not looking good at the moment.

I'm not sure I can even just call a scrap man as all of the documentation for it is in a folder somewhere in the depths of a storage unit!

Are there any gotchas for removing the becm? I've found a guide which seems to suggest that it's quite straighforward but it's one area that I've never played with so I'm a bit nervous...

My other half thinks we should just cut our losses and I'm really beginning to feel the same way. If I had the time and the space to persevere I'd be much more comfortable about it, but these things are just impossible to manage when they're completely immobile!

Sounds like you have a lot going on at the moment at home! The least you want is this P38 causing more pain

What's the year / model?

Id cut your losses, get rid and then think about possibly getting another one if / when you have settled in.

It sounds like major electrical failure of some sort

Good luck !

2.0_hippo said:

Sounds like you have a lot going on at the moment at home! The least you want is this P38 causing more pain

What's the year / model?

Id cut your losses, get rid and then think about possibly getting another one if / when you have settled in.

It sounds like major electrical failure of some sort

Good luck !

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Believe me, I'm seriously considering it.

It's a 98 4.6 HSE. It's generally pretty ok, just a bit sorry for itself at the moment. As you say, too much going on at the moment and now the water cylinder upstairs has started leaking. Joy.

Sandhurst isn't far from me, I could tow you a few hundred yards if you want!

Saint.V8 said:

Sandhurst isn't far from me, I could tow you a few hundred yards if you want!

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Seriously? Incredibly generous offer! I might take you up on that, although the new parking position is behind houses so would need pushing too...

I might crack on and pull the becm today. Figure I've got nothing to lose since it's dead anyway.

You sure it isn't just RF receiver draining the battery and that is causing the rest of the symptoms?

Grrrrrr said:

You sure it isn't just RF receiver draining the battery and that is causing the rest of the symptoms?

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I thought it might be a battery problem up to yesterday but connecting a new battery and having the engine start cranking on its own suggests Becm to me.

Unde rbonnet fuse box affected by damp as a result of not being used.

Datatek said:

Unde rbonnet fuse box affected by damp as a result of not being used.

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It's just had a brand new fuse box as a result of it losing all electrical power during work for its mot Keith. The old one was a bit burnt apparently and the starter relay had melted...

you can as a quick temp fix disconect the feed on the starter from the fuse box, connect another lead to it with nut and bolt run lead into car through a swicth an back to starter then to start car throw switch turn key then throw switch to off , dont forcet to insulate wire thats bolted, will get you out of trouble for now.

kooky_guy said:

It's just had a brand new fuse box as a result of it losing all electrical power during work for its mot Keith. The old one was a bit burnt apparently and the starter relay had melted...

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I can't see that the BECM can affect involuntary operation of the starter motor.

Datatek said:

I can't see that the BECM can affect involuntary operation of the starter motor.

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Oh. I wasn't sure what else it could be. Apparently the melted relay was stopping it from operating at all previously, and that combined with the mindless cycling of the door locks immediately made me think becm.

What else could be causing these symptoms? It's been standing for a couple of years although the electrics have been kept up with a maintenance charger and it's been run every so often. It has become rather damp inside - I had to replace a couple of switches that had died.

Apart from the running problems documented in my other threads, it was running quite happily 3 days prior to yesterday and had been on the maintenance charger in between.

kooky_guy said:

Apart from the running problems documented in my other threads, it was running quite happily 3 days prior to yesterday and had been on the maintenance charger in between.

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Might be an idea to either put a dehumidifier in it for a couple of days. If BECM is damp you will get all sorts of problems as the electricery takes short cuts around the boards. May just need drying out. Take it out and put in in a warm place for few days. Or dry it out by lighting a fire on the back seat.

I'm almost at the poi t of disconnecting the Becm but thought I'd investigate a bit more first.

Have pulled the starter relay and left the battery on. Just waiting the 30 mins for the key code lockout to expire then will try swapping the relay with another.

All else seems happy enough now a good battery is back on...

Keith's got me wondering now if I'm just jumping to conclusions about the Becm...

The BeCM gets the blame for a lot of things and I'd say 75% of the time the BeCM is innocent!

And, yes, if you want a tow and a push (not as fit as I used to be) just let me know and will agree a mutually convenient date!

Well this just gets weirder.

I swapped the starter relay for one for one of the window demisters and that's stopped the starter cranking on its own.

In fact, once I'd put the eka code back in, it all starts and runs quite happily.

If I hadn't already taken the seat out I would have driven it round to my other parking spot as who knows what it will do next time!

Unfortunately I've not got an avo meter to hand, but I'm guessing the original starter relay has stuck closed. Now why would it have done that? Or how? I assume the starter relay isn't supposed to be anything different to the other yellow ones?

Is it worth doing anything else with the becm in the meantime? I'm temped to put it back together enough to move it and then think some more. I dare not leave the battery connected though after what it did the other night. I'm not used to having neighbours, but in all the time I lived in the middle of nowhere the alarm never went off and I've never seen it do the door lock thing before either. I'm really hoping that it's entirely down to the old battery being a bit iffy...

In the meantime I've got some plumbing to do!

Really appreciate your offer Saint. Will let you know if I need to take you up on it but fingers crossed...

Normally door locks would be a microswitch thing. Unrelated but unfortunately for you, coincidental. The problem is inside the driver's door lock mechanism. Its just worn and flops around. Now normally this happens when driving (as it gets jiggled around). That its doing it parked up suggest errant voltages which I can't guess at. RF receiver? I'd take the pad off and give it a good spray around with contact degreaser etc anyway and I'd do the front passenger side door lock too for good measure. Note if the micro switch is worn it'll eventually need changing.

Battery going flat,'door locks cycling and now having neighbours all points to the RF receiver.

Quick update.

Just went back to it. Put the seat back in.

As soon as I reconnected the battery, the starter began cranking.

Tapped the 'new' starter relay and it stopped.

I'm starting to think there's a fault with my new fuse box. Considering how expensive it was, I'm somewhat irritated. Can it be anything other than the fusebox? Dodgy connector? Is it easy to check these?

Still, I did manage to move it so at least I've got 6 weeks before I need to play musical chairs again. Phew.

Really appreciate the advice and help so far guys!