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Alarm UCH Connections (Any Fitters About)

  BMW M135i
Please bear with me here as this is a bit of a mammoth post but I want your opinion as to whether you think i'm right much as anything else.

Righto want an alarm and considering what I can get the alarm itself for and compared to the fitted price i'm going to fit it myself.
Not really bothered about the fact that it won't be CAT1 certified just want an alarm that works and it'll give me a nice project to keep me entertained on a saturday.

I'm going for a Cobra 3868 ( nothing fancy just a simple 2 to 1 upgrade jobbie, mainly going for this one because it works off the standard renault plip rather than having to have an extra one.

Got hold of the Cobra fitting instructions and how to program the alarm to recognise the plip etc but the stumbling block i've came across is that the fitting instructions tell me to connect both the negative and the ignition live to the same wire on the UCH loom.
I've got the wiring diagram and pinouts off dialogys which makes it pretty damn straighforward id'ing which wire is wire, now the instructions tell me to connect the ground to A4 on the UCH P202 connector it also says to connect this to the ignition too :S.
Looking at the actual connector and checking with the pinout A4 is the ignition live signal and the ground is B6, now the cobra instructions tell me to connect the ignition to a Yellow/Violet wire which A4 is and the ground to a black wire which B6 is.

What i'm asking is that I assume the Cobra instructions are wrong because there telling me to connect two wires from the alarm to the same wire on the UCH but get the colours right which must be wrong as A4 is certainly not a ground. In my mind I should just be able to connect the ground to B6 on the UCH which is a (the only specific) ground and all should be fine yes ?

Hope I didn't loose you in that mammoth post lol, i'm after opnions as to whether it makes sense to you as much as a definite answer so just post away. :)
  BMW M135i
Also does anyone know where the siren is installed with the standard fit alarm in the Mk2 Ph2 ?
  BMW M135i
Will try that and see what they say, in my mind it should work ok but just wanted to see what other people think.

Also, other than scotch blocks how can I connect the alarm to the UCH loom? would like to go for the as cleanest pro look I can.
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  Carrera 4S. Clio 172. M5
The instructions from Cobra have been rubbish since they started importing them in 1970. They are translated ?? to English by an Italian roadsweeper.

What you might find is. As the switched ignition wire on all cars rests at ground when the ignition is off, the alarm needs that ground connection to know the Ign. is off.

I made a promise to myself I would never fit another Cobra alarm as long as I had my eyesight because of their dealer back-up (or lack of) so I stopped doing so about 8 years ago, so I cant tell you for sure if this is correct for this alarm.

I dont think any of the good dealers fit Cobra any longer for pretty much the same reasons.

All I can suggest is you try it with a very low rate fuse (2amp) in line and see what happens. But at your own risk.

Good luck.
  BMW M135i
Yeh I can see that, its just that every other installation for the alarm i've looked at says to put the wire to a ground on the body and as it says to go to a black wire too i'm thinking its more than likely a mistake than anything else.

Looking at the Kangoo manual which is similar to a Clio in the fact that it uses a UCH and has a similar/identical pinout says to ground it.

Hmm, have emailed the uk distributors of Cobra who say they'll answer any questions but i'm not holding out.
  Carrera 4S. Clio 172. M5
bmh.01 said:
Also does anyone know where the siren is installed with the standard fit alarm in the Mk2 Ph2 ?

Remove the wiper arms, the plastic panel under them and the siren is tucked under the wiper motor. If you want to get it out, remove the washer bottle and the wiper motor.:cool: