AudiWorld Forums - RESOLVED - Water in Passenger Side (front and rear) after rain

Okay, I'm writing this for the benefit of others who may encounter this situation.

My 2005 allroad 2.7T Auto was parked in the driveway when there was a heavy thunderstorm. Next day morning, I started the car for work, din't notice anything unusual and hit the roads. After the first mile, I was in a signal and was pulling up on green and there was a thud and a jerk, same time, I heard splashing water on the rear passenger side and multiple bleeps and blinking lights on the dashboard. I think the car went into limp at that point (I continued driving for fear that if I stopped I may not be able to start again - look at my other thread on this). After reaching my destination (work), I checkout out

ABS light ON
BRAKE light blinking
CHECK-ENGINE light on
- P0778
- P0748
- P0886
- U0101
- P2716

I called an Indy shop who asked me not to drive the car and bring it to shop 2 days later (they were busy). That evening, I brought the car back home (against the shop's advice) driving in limp mode - overall I had driven about 18 miles on LIMP, car jerked heavily a 3 or 4 times on the way home, fingers crossed that I din't damage anything permanently. Once home, I removed the passenger side carpet (did not drop the glove box) and pulled the black-box (submerged in water) which held the TCM. Removed TCM, dried it and left in a cool dry place in my desk. This is appx. 24 hours after the rain. Sponged off most of the standing water from under the carpet and left a dehumidifier running over-night. Next day morning, checked there was more standing water as the carpet padding continued to drip water. Sponged out the standing water again. Left a small fan blowing air into the carpet area and left for work in another car (I had brought a new Q5 only 7 days back). That evening, 48 hours after the rain, I tried to hook in the TCM to check if it was salvageable. Disappointed, nothing changed except the blinking BRAKE light is not there anymore, all others (check-engine, ABS, Tranny LIMP) still glowing bright. Pulled up the carpet further to the front and found another module. It was the ESP module under a plastic sheet. Took the TCM and left it in a bag of rice. Please note that I did NOT remove the TCM metal casing to expose the motherboard. Next day it was sunny and dry with temp reaching 90. Started the car in (plugged TCM) and backed it into the driveway in (still in LIMP), open the doors, sun-roof, carpet a further and left it for the day. Left the TCM again in the rice bag. That evening, 72 hours after the rain, plugged the TCM (took it out of the rice bag) and started the car. What a relief - no ABS light, not in LIMP anymore. Cleared the codes using Torque App and drove for a couple miles and parked it again. So far, so good. I'm yet to take it for a spirited ride, but it seems to be working fine now. I will continue to update this with whats happening in the next few days.

What I learnt
1. Do not lose hope if your TCM or ESP module is wet and is not working. Just give it some time to dry and keep trying for a few days. It started working for me after 3 days. I was blessed to have another car for work that I had the liberty to wait and let it dry.
2 Reading the forums, there seems to be a confusion on why ABS light is glowing while the ESP module is wet? I initially thought what was higher up in the passenger foot-well is the ABS module, but I was wrong. The ABS module is near the Windshield wiper and it was dry and was good. Looks like when the ESP module gets wet, it may also throw the ABS light.
3. I did not open the metal housing on the TCM module even though it remained soaked under water for about 24 hours.
4. My sunroof drain was not blocked. The drain under battery is fine. 2 years back I had a basket ball hoop fall on my windshield after a thunderstorm and I had hired someone to replace the windshield. I think the plastic cladding under the windshield is not secured well enough that water entered it and into the cabin air filter housing. This is a theory as I see the sponge in the filter housing to be completely wet and deteriorated. There is also a crack on the filter housing base. Not sure whether water would have entered if there was not there. I can also feel some wetness behind the glove box when I put my fingers from under the passenger foot-well. I'm continuing to test this theory to find the reason why water entered.

Tips from others are welcome. I'm not very mechanically inclined, just can handle wrenches. I may be doing some silly things here, so, let me know if I'm missing anything here.