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#5059 - 03/12/21 12:39 PM If Your C8 Takes a Leak on Carpet - TSB  
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teamzr1 Offline
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GM has issued a new Technical Service Bulletin #N212327740 for some owners of 2020 and 2021 Corvettes
over an issue with the HVAC condensation drain hose.
The bulletin states that these drain hoses may not be fully installed, which is causing water leaks in affected vehicles.

GM will flag those affected cars within the Global Connect system which alerts dealers to check the hose next time the cars are brought into the dealership for service.

If your 2020-2021 C8 Corvette does have this problem,

you may see wet carpet as the water leaks out and accumulates in the passenger side footwell.

Service technicians will review those cars by removing the front floor side console trim panel,
peel back the carpeting and reattach the hose to its proper position if it wasn’t fully seated into the drain how


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#5273 - 09/17/21 02:57 PM Re: If Your C8 Takes a Leak on Carpet - TSB [Re: teamzr1]  
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This quality control issue was not the total problem and exists in both 2020 & 2021 model years

Turns out another screw up as to welds to seams in the floor did not get done correctly so instead of the correct fix BGP put a patch over the seams
& also did not install a hose on the coupler that goes to the fitting the TSB was all about

So water from using the A/C (& more A/C is used, then more water draining) runs down that coupler to under side of passenger floor
and is blown rearward to where the patch and seam is, water runs under the patch edge, through the seam and back up onto top of the passenger floor
and soaks carpet & if not caught will grow mold mad

If not wanting some dealer to screw around with your C8 or joyride it :-)
take off under tray and below floor on passenger side you will see (as below ) that drain coupler, patch and seams

Use like a 15 mm OD hose that fits well into that coupler, hose long enough to carry water out to ground
Use a good weather sealer to assure the seam and patch (if installed)

Attached Files acleak1.jpgacleak2.jpgacleak3.jpgacleak4.jpg

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