From the March 6, 2013, Wheels section in the Dayton Daily News:
Reader asks about a flood-damaged vehicle
Even though the circuit boards of the computers and modules are usually sealed, the connecting wires and terminals are exposed and can be easily corroded if the vehicle was flood damaged.
Wheels: Dike I. writes by e-mails:
"Could you advise me please? My brother bought a flooded Audi S4, 2012 model. I need to know procedures or guidelines on how to fix a flooded car. Is there a manual or web site for it? I just don't want mechanics to mess up the car while fixing it. Thanks a lot in anticipation".
Halderman: Boy, oh boy. I hope he did not pay much for this car. When a vehicle is under water, even if it only came above the floor, many faults are likely to occur, mostly electrical.
If the water reached just the carpet, there are many electronic modules and wiring that are located along the side rails and under the center of the vehicle. These modules are not water-proof and are not designed to be exposed to water. There could be 30 or more of these electronic control modules in this vehicle. All of the electronic modules will have to be replaced because even though electrical devices, such as the radio and power windows, may work shortly after the car is dried out, corrosion will eat away at the wiring and the connectors.
If the water got as high as the top of the dash, or if it was salt water, then everything electrical in the entire vehicle is ruined. About the only thing that can be done to get some of the "investment" back is to strip everything from the vehicle and sell the sheet metal parts. Even the engine, transmission, and wheel bearings will likely need to be replaced or an expensive overhaul will be needed because water gets into these components through the vents.
The car should have come with a title that indicates that it is a flood damaged vehicle so selling it will be either impossible or illegal. Long story short; a flood damaged vehicle will never be right again.
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