MX-3.com

97 UK 1.8 V6 with factory fitted immobiliser. I have just got car back on the road after being out of action for 6 months, the immobiliser and remote central locking are not working correctly. Sometimes it activates after a few tries, takes quite a few attempts to de-activate. Central locking works with key in lock. I've tried both remotes and it doesn't appear to be the battery. Can anyone point me in the location of the receiver?

hiya,
First off have you checked the keyfob battery?
As far as I'm aware the UK MX3 didnt come with remote central locking...central but not remote unless someone else can clear this up.

Had a poke around under the dashboard and by the look of the wiring, you are correct it's not factory fitted. Have changed batteries in both remotes. The immobiliser make is Sigma model SG2. Removed and reconnected immobiliser unit, connections all seem fine.

Well I'm afaraid my auto electrical skills end there lol. If I were you Id try and use a multimeter and see if all the connections are working- you need to try to find what circuit the door release is on and if power is getting to it. Check all ure fuses, obvious I know but still. If you get no joy then i'd just get anotyher RCL kit and fit that- less than 40 bucks off ebay and save alotta hassle.

Thanks, fuses checked ok and voltage supplies seem fine. Probably will end up having to change it.

This might sound silly - did you check the antenna on the receiver unit? Its usually just a wire hanging down from the receiver unit. A while ago my mechanic wrapped and clamped that wire to a nearby harness and from that point the receiver had trouble communicating with the keyfob. If you are in the same situation try getting that wire/antenna loose and find the best position for it to receive.

Thanks, checked the antenna. Antenna is not clamped to the wire harness. With the remote beside the antenna it still doesn't work.

You can probably check all the wiring for loose connections or breaks (at the joints) etc - If that checks out then it probably is a component problem in the receiving unit - you can try opening it up (it probably is hermetically sealed) and look for visible damage or loose connections or stuff like that. But odds are you might have to replace the whole thing.

Thanks, some of the connections just had the wire ends twisted together. Checked them all and soldered them for a better connection. Receiving unit case screwed together, no visible faults or dry joints. All components seem intact. I'm wondering if the receiver needs reprogrammed to the key, haven't been able to find much info on this make of alarm.

EricW wrote:Sometimes it activates after a few tries, takes quite a few attempts to de-activate.

if it works sometimes - then it probably is not a key code issue

Here's the sigma website
http://www.tg21plc.com/distribution/vtd ... /index.php

There is a (pay) site for dealing with alarms
http://www.piranha-uk.co.uk/