BCU Repair or Replace?

I've got indicator issues (constantly indicates left) and central locking issues (randomly unlocks itself).

I've replaced the IDM and checked out the wiring. Found afew dodgy looking earths which I've replaced and also removed some spurious wiring but I'm still having the issues. I've no access to diagnostic equipment but I've got to the point where I'm fairly confident it's the BCU that's at fault. I've removed it and inspected it but there's no sign of damage, damp or corrosion so I imagine it's a chip fault somewhere inside it.

I've found a place on the net (Turner Diagnostics) who offer a repair/exchange service which works out at about £170. Seems fairly reasonable considering there's no programming involved. Has anybody had experiences with this company?

The other option is to source a second hand working unit, and use the cash saved to put towards a nanocom/hawkeye so that I can program it in.

Any thoughts/advice on the best way to go?

Rick the pick on here is the BCU god if your unsure contact him he can repair refurbish and test and return for you

The BCU is not the average repair job, it is a very complex board with surface mount electronics and a large Motorola DSP sat in the middle.

If you can find someone who can repair it, go for it, but get some kind of 'no cure no pay' deal first.

Plenty around on fleabay, I have got a spare here just in case, but hope not to need it.

Peter

Jaswilliams said:

Rick the pick on here is the BCU god if your unsure contact him he can repair refurbish and test and return for you

Click to expand...

Thanks for that, I've sent him a PM.

listerdiesel said:

If you can find someone who can repair it, go for it, but get some kind of 'no cure no pay' deal first.

Click to expand...

From what they say on the website, it looks like Turner Diagnostic will look at it, let you know a cost then send it back to you if you don't want to proceed. I would expect that the repair would be covered by some sort of warranty too.

The problem is intermittent, it occurs 90% of the time, but the odd time it will have a good day. I just hope I don't send it in, the BCU has a good day and they find no fault with it!

it seems like a dry joint in the circuit or external wiring/contact issue, which is quite common unfortunately, that's why IMO if you can afford you better get a cheap used BCU and a nanocom, cos if it's some external datalink issue by sending the BCU to T.D. you'll pay at least for postage(though i dont think they wo'nt charge you for diagnose) but still not fixed, getting a replacement BCU even if the other one is good at least you have a spare and nanocom will be a good investment anyway, if the replacement BCU will cure it then if you have a friend who is familiar with electronics you can investigate the old BCU yourselves cos if it's a dry joint you may find it. ... That's what i'd do

Looking at the corrosion on the ones I have here, it might be worth removing the BCU and getting a fine brass brush inside to clean the pins up, then a bit of contact cleaner before fitting the thing back again. Just removing and refitting may be enought to wipe the contacts.

Peter

sierrafery said:

it seems like a dry joint in the circuit or external wiring/contact issue, which is quite common unfortunately, that's why IMO if you can afford you better get a cheap used BCU and a nanocom, cos if it's some external datalink issue by sending the BCU to T.D. you'll pay at least for postage(though i dont think they wo'nt charge you for diagnose) but still not fixed, getting a replacement BCU even if the other one is good at least you have a spare and nanocom will be a good investment anyway, if the replacement BCU will cure it then if you have a friend who is familiar with electronics you can investigate the old BCU yourselves cos if it's a dry joint you may find it. ... That's what i'd do

Click to expand...

Any common areas to look at for dry joints? I'm hoping the IDM replacement has ruled that out, and the wiring in between looks ok from the parts I've seen, but are there some headers or other connections that you know of that I should have a closer look at?

If I go down the replacement BCU and nanocom route, does it need to be nanocom rather than hawkeye? And do I need to make sure I get the EKA code for the BCU for programming?

listerdiesel said:

Looking at the corrosion on the ones I have here, it might be worth removing the BCU and getting a fine brass brush inside to clean the pins up, then a bit of contact cleaner before fitting the thing back again. Just removing and refitting may be enought to wipe the contacts.

Peter

Click to expand...

Will give that a go, can't hurt can it! Thanks.

the dry joints are usually at the margins of the circuit boards, or where two boards are interconnected, or where "harder" connections are, there's no rule for that

as long as the BCU is in working order after you sync'd it with the engine ECU immobiliser and the keys you can read and insert your own EKA(only with nanocom, hawkeye can't do that)... the EKA feature can be disabled also but you better have it

It has been said that Turner Engineering just forward the BCU to Rick. Nanocom is better than Hawkeye IMO.

I've just PM'd you Phil with my thoughts regarding Turners.

I test for free, just pay the postage. The mileage cannot be altered on these BCU's so be careful regarding a used BCU's mileage.
You're more than welcome to send it down & I'll test & re-flow it for you, & you'll only pay if I find a fault that I can repair.

Just replied Rick.

I'll have a quick check over this evening and if I'm still no further I'll send it down to you.

Much appreciated!

Cleaned the bcu and all the connectors - no difference.

A couple of wires going into the brown plug don't look great though so it might be worth rewiring that. Anyone know if you can buy the brown plugs on their own?

:nopics:

Here's the wires going into the brown plug connected to the bcu:



The bare conductor that's showing was dry and had a powdery coating before I sprayed it with contact cleaner. They seem tight into the connector though. Will find out where the other end is tomorrow and if possible meter the resistance between both ends to see if its causing a problem. Inside the BCU itself looks fine so didn't bother taking a picture of that.

The scorching to the white plastic is from me trying to get solder between the wire and spade, but it wouldn't stick. Needs cleaning up better with sandpaper.

or use plenty of flux.

It's developed another problem now - immobilisor isn't disarming and remote locking doesn't respond. Changed fob battery, it worked once and now it's stopped again. At least it's got me home anyway!

I'll be sending the BCU to you next week Rick...

be aware... dont remove the BCU in immobilised status cos then i'm afraid it becomes useless.

Sounds like I'm screwed then as pressing the button won't deactivate the immobilisor and I have no EKA code for it.

Guessing I'll be needing a replacement bcu and all that goes with it?

Ask that Rick guy if he can do something with a "locked" BCU or not... if he can't you have a last chance to contact a main dealer with a proof of ownership and they'll tell you the original EKA... but IF the BCU is fubar'd bad or the EKA was changed at a moment only other good BCU will help