Alarm progress and appreciation

[Robin]

First a huge 'thank you' to you for contributing to the answer to my alarm problem on my 97 build Xantia 1.9td.
I have now isolated the problem down to the sensors fitted in the doors and replacements are on their way to me.
Originally I could not isolate a single cause so this is what I have done to achieve the result.
Check the central ECU under the seat and remake the plug connections to ensure full and clean contact. Test and found fault continued despite isolating interior sensors.[:(]
Remove, clean and remake all door switch connections to ensure soundness of electrical connections. Test as above and alarm sounds.[:(!] Isolate cabin sensors and all is well.[:D]
Note for the record. The Citroen Parts Centre near me is a big one and reports a flurry of sensor sales over recent months to owners of cars around four to five years of age. Is there a message here[?]
A pair of sensors costs £23.
Next to have a go at my clutch[:(]