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Is it possible?(check engine light)

So after getting a right axle changed on a 2008 Sonata my bloody check engine light come on right after leaving the repair shop at closing. 5 minutes later at home I checked under the car to see the axle repair and noticed a water dripping from the back of the engine. It only lasted a few minutes. So the next day I had the engine warning light coded and it turned out to be a’ heated oxygen sensor heater control circuit low.’ From an auto code website:

“Water getting inside the heated oxygen sensor connector can cause the heated oxygen sensor fuse to blow, which is a very common problem
for this type code.”

The water was dripping right below where the oxygen sensor is located. It wasn’t raining that day.
Could a repair shop accidently or worse yet cause this to happen to increase repairs. How would you proceed at the repair shop?


The dripping water could be from the ac condensation drain tube

you said “water was dripping right below where the oxygen sensor is located.”

In that case, because the dripping water was BELOW the sensor, there’s no way it got inside the connector

FWIW . . . oxygen sensor heater circuits commonly fail after several years. In fact, it’s one of the the most common repairs. Just replace the sensor and move on

Bottom line . . . don’t bother complaining to the shop. Sounds like they did nothing wrong. Sounds like they have nothing to do with your check engine light being on

I haven’t turned on the AC yet this year? My intent was that leak was dripping to the ground below the sensor but originated above the sensor from ABOVE the engine. I dont know if the starting point of the leak was above or below the sensor. AND the light WASNT on before I left the car at the shop.


You sure it’s water and not coolant?

FWIW . . . on many cars, the ac compressor engages when you hit defrost

what’s right above the sensor?

Anyways, I stand by what I said before . . . oxygen sensor heater failures are some of the most common repairs, and usually have absolutely nothing to do with any botched repairs

Maybe they had to disconnect a heater hose or something to get needed access for the axle repair. Or maybe the tech spilled some water from his water bottle. Who knows? Either could explain the water dripping. As long as it isn’t dripping now, and the coolant level is ok, I wouldn’t be overly concerned about that.

O2 sensors can have small holes in them to allow gasses to flow between the sensor material and the outside air, so they can be damaged by liquids spilling on them. Usually it is gasoline or oil or grease. But maybe water can damage them too. You’d think they would be pretty immune to water spills b/c of splashing water under the car when driving in the rain doesn’t kill them off.

I’m with db4690, best to just figure out what’s causing the light to turn on and fix it. An O2 sensor has circuitry which heats it, and other circuitry which senses the O2 levels. So the problem could be in either of those, or the sensor itself. An experience tech should be able to figure it out w/o much trouble. As db says above, O2 sensors are a common problem and easily fixed.

In the VAST majority of cases, it’s been the sensor itself

At least in my experience