Car alarm activates when raining

2011 TSE boot leak rectified and sensor under warranty I believe. Last 2 days it has gone off 5 times after heavy rain. I found this below in an other thread but wondered if any one had any other ideas. Car is due to go and be checked Monday by Wilcox of Wickwar, good dealers.

Quote:

No, the alarm problem came later - it was checked, the battery was not being drained of power (other than normal limits)... It turned out that the Siren unit was not drawing power to maintain the self contained back-up battery - which then went low charge

from the last news http://ift.tt/1z6DSYr

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