Might be too late if you've had it sorted but the module is under the front passenger carpet. If you take off the cill cover and front passenger doorbell plastic trim, you'll be able to prise up the carpet and pull out a black plastic box the size of a video cassette case. The module is in there. You can just about drive with the box above the carpet until the leak is sorted.
I've had lots of experience fixing this on a few C5 models so feel free to pm me and I could pass any info over the phone.
Grant
|