Adding Remote Central Locking

Adding Remote Central Locking

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Stepsie

Original Poster:

2 posts

55 months

Monday 13th April 2020
quotequote all
I thought a nice job to do during the current lockdown would be to fit a remote locking kit to my partners 2004 MX5 2.5. I know 100% it is a 2.5 and it has central locking as standard which operates from both doors and it has the module under the steering column.

What I thought would be quite a simple job has turned into a real headache so I have come here for some advice.

The kit I purchased is the cheap eBay kit which many people seem to have purchased, but I am struggling to work out what wires I need to connect to the white & white/black wires which are the lock & unlock signal.

Reading through various other threads and forums there are lots of information, but noting specific about wire colours for tapping etc. I have located the factory central locking module under the steering column, but the only thing I can get from that is a 12V feed. I don't have a multi-meter, only a test lamp and apart from that all I managed to get when I touched my test lamp probe into a red wire the locking tried to lock. There are two red wires in that loom, one that triggered the locks when I touched it (the door was open so I don't know if it was trying to lock or unlock) and the other that did nothing.... could these be the wires I need. It does seem odd that they are both red though?

I did read on other posts that all that's needed if the car has central locking is to bridge one of locking wires, but I'm not really sure what that meant? Another post said they disconnected the plug from the factory unit and just used the eBay module, the post has links to photos but again no specifics about wire colours etc.

Any help is greatly appreciated.
Thanks.

WhatamIgettingmyselfinto

64 posts

91 months

Monday 1st June 2020
quotequote all
I guess you are looking to replace the existing module with the new remote one?
On my Mk1 the green and blue wires actuate the servo (not sure if these were aftermarket), with the remaining 3 used for lock and unlock signals. You're going to need to work out what does what, if you wire the signals wrong, all that will happen is the doors will lock and unlock repeatedly until you disconnect. You will have to cross reference some wiring diagrams (if provided) and work out what to do.

I guess it would be possible to piggyback the remote system onto the old one to reduce the amount of work.

Stepsie

Original Poster:

2 posts

55 months

Tuesday 2nd June 2020
quotequote all
I've tried all kinds of combinations and the nearest I can get is that I can hear the new module relay clicking when I use the remote, but nothing happens.

YouTube clips that I have viewed make it look so simple, but the wiring is so tight and thin that I am wary of damaging things.

WhatamIgettingmyselfinto

64 posts

91 months

Wednesday 3rd June 2020
quotequote all
If it clicks when you blip the key and nothing happens then you don't have the right wires hooked up to the servos. Two of them will pulse to I guess 12v or ground depending on whether locking or unlocking. Find these two first and make sure the servos work, then work out the other wires. Once you trace the first two it will be plain sailing.