Technical Is the 'body control unit' also the passenger fusebox?

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Technical Is the 'body control unit' also the passenger fusebox?

boguing

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I'm about to hack into the central locking harness, and if the BCU is also the fusebox then I think the plug for the locking must go into the back of it (back as you look at it in the car, front actually). I'm dreading this job really because it's almost inevitable that it's best done sitting upside down on the driver's seat, head down in the footwell as usual for these things. If I'm aiming to take out the wrong box I'd kinda like to know now!

(I didn't get the remote key from the last owner so bodging it with a Chinesium £10 jobbie).
 
The central locking is controled via the body computer(BSI) next to the obdii diagnostic port

It's pretty well protected, but I can not stress enough, don't mess it up,

A damaged (BSI) is not cheap or easy to replace

The BSI is the immobilise, a secondhand one will not work without reprogramming,


If the car is an early active, there might not be a motor or wiring in the drivers door for the remote locking as its wasn't needed for manual central locking
 
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The central locking is controled via the body computer(BSI) next to the obdii diagnostic port

It's pretty well protected, but I can not stress enough, don't mess it up,

A damaged (BSI) is not cheap or easy to replace

The BSI is the immobilise, a secondhand one will not work without reprogramming,
Excellent, thanks. Upside down in the footwell it is then.

I'm just going to splice into the pairs of wires that supply +/- 12v to the actuators and steal 12v from somewhere with a piggyback fuse.

I'll unplug the locking harness from the unit and disconnect the battery to work on it, then decide whether or not to plug it back in. If I don't I'd lose the central locking from the driver's door key switch, but it would protect the BSI. I'll guess that something in the software might get tetchy if there's no harness connected but I can't imagine that it'll affect anything - and I'll experiment with that before I start splicing.
 
2004 1.2 Dynamic
2004 remote locking was an option extra, there is a good chance it never had remote locking

The door switches and motors go everywhere on the BSI

There isn't one to unplug

Have to think how you can move forwards
Back shortly


Screenshot_20240216_112716.jpg
 
I've got this little oddity where F38 should be -the hopeful thing is that it's a 20A fuse, as it would be for remote locking.

Also, that plug next to it looks like it's got grey and yellow wires, and they're the ones I'd need for the doors according to Haynes anyway. (They may of course be two colours with the stripes hidden to confound things).

1708086025333.png
 
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F38 should be a 20A it should be the relay in the body computer that powers all the door motors

The motors do not just go into one connector the in M, E and H

Fiat often share fuses, you will have to pull F38 and make sure there's no adverse effects
 
F38 should be a 20A it should be the relay in the body computer that powers all the door motors

The motors do not just go into one connector the in M, E and H

Fiat often share fuses, you will have to pull F38 and make sure there's no adverse effects
I've added the picture that I forgot from the post above.

I really appreciate your knowledge here - but does it stretch to where I might find pinouts for the body unit? Haynes gives me these from 1-36.

1708086561353.png


Also M, E and H, wossat?!
 
However to me you are looking at the problem wrong

The boot is probably missing wiring, button and motor

The drivers door I probably missing wiring and motor


Reinstate the missing wiring and motor into the drivers door

Add a third party remote to command the central locking to work and it works fine of the remote or key

If you want the rear hatch to work that a bit more complied the handle and latches also need to swapped over
 
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Lightbulb moment. The Haynes diagram above labels A, H, M, I, G and E in the image above. As you say, all over the place.
Yep

It's been done a few times before

By adding the missing wiring and a third party remote

And

Using a third party actuator and remote

Let's see if I can dig out the threads

Don't forget about your insurance
 

A few different ways on here
 
I've just checked the car. No motors - as you suggested.

I wonder why the previous owner said he'd lost the remote key?

Thanks again for the advice but it's not really worth the faff or expense - I had some spare remote switches and relays and thought it would just be a quick soldering job.

Disappointing but I have an Alfa that can have my weekend instead.
 
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