Alright guys hopefully this shouldnt be too hard to figure out for you guys.
My brother got his 1999 c5 corvette 4 weeks ago i was driving it one night during a thunderstorm(stupid me) and anyways on one street there was 3-5 inches of water i drove through it. Although the vette is lowered it wasnt high enough to reach to exhuast. anyways i got to the gym parked and after 2 hours i got done i went home no problem.Next day brother takes out his car and its all wet on drivers side from pedal all the way to the back and wet only a little bit on passenger side. while driving he got the dreadded reduced engine power sign.

codes-
p1120
p1221

tcs-c-1255
c1276
c1278
u1016

bcm-u1016

sdm u1016
ipc u1016
ldcm u1016
rdcm u1016
rfa u1096



So i read that the pcm is under the battery of the passenger side fender. made me think the pcm got wet. took it out sprayed maf sensor cleaner on plugs and pcm wiped it down and that didnt help. i had already dried out both the driver and passsger side by remoxing carpet and using the heat gun. so considering the rep came up right after teh water im thinking its the computer on the passenger side foot well but that wasnt wet at all or the gas pedal. Help me out guys what makes it worse is that this is my youner brothers car not even mine and hes 19. im getting heckled as i should be. i cant seem to find any good threads or stickies in diagnosing rep light.thanks guys

 

C5s are bottom breathers, so perhaps sucked a quantity of water through the intake, which may be setting some of those codes.

The TC/ABS computer is low in the front off-center on the drivers side.

There are a number of different ways water could get inside the car just from the rain, much less driving through a mini-lake.

 

After drying out the TC/ABS computer if im still gettting the same exact problems what would do you think i should check next or replace.
and yeah i had a bad feeling while driving on that street but there wasnt really any turning back at that point.......

 

Did you clear all the codes using the DIC? Then take it on a drive and pull the codes again b/4 you shut it off

 

IF,,,,,,,,,,,,,,,,,,,,,,, You had / have water in the passengers foot well, The Body Control Module probably got wet!

THE BCM DOES NOT LIKE WATER/MOISTURE! PERIOD!


RECOMMENDATIONS!

Disconnect the battery Neg Terminal. Remove the BCM. Place it in a very warm DRY area. An oven with a temp at about 110-120 deg is good.

Let it get COMPLETELY DRY.

While its drying, remove the seats and carpets and DRY them out! If you don't, they WILL Mildew and smell very BAD!

Reinstall/ Reconnect the DRY BCM, Re-connect the battery and CLEAR ALL THE DTCs!!

Then see where you are at. Bet ya its all better!

 

I had the same thing happen but it was from the udders that collect and disperse water under the wiper cowl. I did this method but used my lowest oven setting (200). Cleaned the udders and haven't had an issue since.