How to remove the ECU
 

I want to get a 160 upgrade via post, so I had to remove the ecu.

The 1st time I done this, I was a little apprehensive, as I don’t like disturbing electrical cables. I didn’t see a “how to” at the time, so this time, I took some photos, which may be of use to anyone else having to do the same.
90% of this should be familiar, for anyone who has changed a pollen filter, or checked their plenum for water ingress, so apologies if photos look repetitive.
Edit: prior to disconnection of electrical connectors, it would be recommended to disconnect the battery. Makes sense to do this at the outset, but unfortunately not shown here.
1st I removed the rubber weather strip.
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Then removed the outer grille scuttle panel by releasing the 2 tangs.
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Unscrew the Philips head screw, that is secured in the plastic scrivet.
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The scrivet should pop out. It looks like this.
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Then remove 3 of the securing clips nearest to the near side wing.
The photo below shows I have started the furthest one.
I use a small flat blade screwdriver, with my finger held over the clip as I prise it up. They have a tendency to fly off.
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The scuttle panel can be lifted up a bit, to remove the inner shield panel, by sliding it out horizontally. It may be a bit reluctant if it has never been out before, but with a bit of wiggling, it will slide out.
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Now you can see the housing holding the ECU.
At the rear of the photo below, you will see a brown clip, holding the 2 main wiring looms to the ECU. This should be unclipped by prising open with a long screwdriver. Mine was already open / broken, so someone has been here before.
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The ECU housing can now be lifted clear of the plenum.
Note the 2 tangs on the front, that secure the top half of the housing to the lower half.
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Take note of how the main wiring looms are secured thru rubber grommets in the ECU housing.
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And the way the rubber grommets interlock can be seen as the housing is opened. This will be important for re-assembley.
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The top of the housing can be removed by releasing the 4 tangs...2 front and 2 rear. The ECU can now be lifted out of the housing.
(I had the ECU out a while back, and had tippexed the no. Sequence of the electrical connectors, to make sure I put it back correctly. I suspect there is only 1 way to fit them, but hey ho, good practice if you are unfamiliar with something😀).
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Electrical connectors can be disconnected, working from 5 towards 1. Connectors 5 & 1 are just pulled straight out.
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Connectors 2, 3 & 4 are disconnected by pressing in a small tang, and lowering a lever arm, to pop out the connector.
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There you have it, the ECU can now be lifted out.
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This would also be an excellent time to check your plenum and / or replace the pollen filter (especially on a diesel) as there is now significantly more room.
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There are separate “how tos” for removal and replacement of the pollen filter, courtesy of Arctic, which I mostly used for this exercise.
Reinstallation should be a reverse of the above, but taking care to reinstall the main wiring loom rubber grommets correctly in the ECU housing.

Sent from my iPad using Tapatalk

Very well done & nicely photographed:bowdown: I'm sure a moderator will be along to put it in the "How To" forum for posterity:cool:

Good point. 👍
Something I forgot to do!
I’d be interested to know if the gurus who do this regularly make a point of doing this.
To err on the side of caution, Ill make sure I disconnect battery before I reconnect ECU.
I’ll edit post to recommend this.


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I never disconnect the battery, if the ignition is turned off there is no problem whatsoever........and I suspect I do this more often than most ;)

A top tip for reassembly is to refit the grommet containing the injector loom to the ECM housing lid before you plug it back into the ECM :)

Brian :D

The interesting point to note is the upgrade can be done by post :}

johnnyd57uk
 

Thank god these extremely helpful pics and explanations are still around. Couldn't find on a general search so switched to "images" and found the thread.

Many Thanks.