Under the circumstances if their tester, likely not the best in the world, said the battery you are driving on needs a slight charge and the alternator (don't much care about the starter given your issues) is fine combined with your tester readings I'd be virtually certain you need a new battery even if it doesn't solve your strange occurrence although it likely will. If you are going to do so and go with the Sears P-1 the sale price appears to only be good for another couple of days; see
viewtopic.php?f=5&t=74244Wet carpet on driver's side I've been thru so here goes:
1. check the passenger side also hopefully it's not wet.
2. check under the carpet on both sides - it's virtually certain the sound deadening mat under the carpet is soggy like a sponge
3. repeat above checks for back seat carpet; should be okay as water does not seem to flow from front to back
4. if the sound deadening mat is wet then the fun begins - remove front seat(s) just 4 bolts and some wiring plugs but best disconnect battery and then remove soggy mat. I cheated; pulled the mat out from under the edge of the center console and simply used a razor type skil knife to cut the mat along obvious lines a bit "up" along the drive shaft tunnel, remove mat and set somewhere on edge where it can drip dry. Prop carpet up as needed and put some sort of fan under it (hair dryer with heat on real low or off works fine). Drip and run fan until dry. Reinstall mat and carpet. I used a bit of tape to cover the razor blade cuts although that was not strickly necessary. NOTE there are some wires running along the floor board in a groove that may need to be lifted as water pools in those grooves.
So where does water come from:
1. obvious passenger side everyone knows about is a plugged AC/heater core drain
2. I have no clue if it applies to the CRD but on my old Dodge Cummins D-250 leaves and other "stuff" had gotten into the cowl in front of the windscreen and migrated into my heater core. In that vehicle I was fortunately able to a) glue window screen to the bottom of the cowl to prevent future problems and b) install a small marine screw top hatch into the face of the AC/heater box so I could reach in and pull out the "stuff". You cannot get to the AC/heater box on the CRD that easily but you can pull the cowl and check from "stuff" pretty easily. Just remove the wipers and gently pull the push pins that hold the cowl in place. I've not done this all the way but I have pulled, as a test, one push pin and it's easy but if you break 1 or more ID Parts has replacements.
3. However, in my case the leak was associated with my sun roof. Partially crud in the sunroof track somewhat obstructing the drain (plastic tubes run down both side window pillars to somewhere below the window) tubes. Clean out the crud and run some weed whacker nylon line down the drain tubes follow by careful application of water to those tubes to confirm they are clear. Something like ice maker water line is small enough to fit inside the drain lines and you can use your mouth (not the best but it works) to send water down the lines. If they are clear then water will obviously come out under the vehicle. While you are at it check the "gasket" that runs around the edge of the sunroof glass to make sure it's intact, reasonably clean, and fully seated. I'll confess while I was doing my first round of cleaning I slightly dislodged that gasket and made my minor problem much worse.