Is it serious if the car's front bumper is submerged in water?
3 Answers
It is serious if the car's front bumper is submerged in water, for the following reasons: 1. Reason one: As long as the water level reaches two-thirds of the bumper or tires, driving through water poses certain risks. 2. Reason two: At this point, high speed will increase the actual water depth the car passes through, causing rainwater to enter the cabin from the engine compartment or chassis. Information about car bumpers is as follows: 1. Function: The car is equipped with bumpers at the front and rear ends, which not only serve a decorative purpose but, more importantly, act as safety devices that absorb and mitigate external impacts, protecting the vehicle body and the safety of passengers. 2. Structural composition: The outer panel and cushioning material are made of plastic, while the crossbeam is formed by stamping cold-rolled thin plates about 1.5 mm thick into a U-shaped groove; the outer panel and cushioning material are attached to the crossbeam, which is connected to the frame longitudinal beams with screws and can be removed at any time.
Water reaching the front bumper can be a serious or minor issue—I once experienced this while driving in heavy rain. Although the engine didn’t take in water, I later found that the front radar occasionally malfunctioned. The mechanic said the sensors inside the bumper were short-circuited due to water exposure. The wiring harness connectors under the chassis also rusted, costing nearly 2,000 RMB to fix. If the water contains sand or mud, it’s even worse—it can clog the radiator and A/C condenser, leading to abnormal engine temperatures. It’s best not to force your way through; if the water level rises further, the consequences could be severe. The safest option is to tow it to a repair shop for inspection. They’ll need to remove the bumper to check the control modules and wiring inside, and clean the drainage holes while they’re at it.
This height is exactly where the chassis wiring and sensors are densely packed. I rescued several similar water-damaged vehicles last year. Corrosion of fog light connectors is quite common, and they usually need to be replaced as a whole set. The air intake is less likely to take in water, but the air filter can get damp and deformed, affecting engine breathing. The ACC radar module inside the bumper is particularly vulnerable to water damage—repairing an OEM part can cost three to four thousand. It's recommended not to start the engine immediately after water exposure; first disconnect the battery negative terminal. When choosing a repair shop, insist on using an endoscope to inspect the wiring harness, otherwise, fault codes might suddenly appear after two weeks of driving. Towing fees plus inspection and repairs usually cost a few hundred dollars, which is much more economical than major repairs later.
