Drove through deep water, now all the warning lights are on...

My father in law drove through a flooded beach road on the Outer Banks, NC, and while the 4Runner did great, afterwords the Slip indicator AND the check engine light came on....

No problems in driving it, however how do I get it to reset, or, does it reflect something bad happend to the vehicle? It's a ~2012 4 Runner.

 

You’re gonna have to find out what the malfunction code is. You might have shorted out a sensor or actuator

 

If you just want to reset the computer, disconnect the battery for a half an hour or so. The computer will reset to factory settings. If the lights pop back on again, then you know you have a problem.

Or, you could take it to an auto parts store and many of them will read the codes for you and reset them.

 

how deep was the water? where do you live?

i'd check the fluids in your Diffs and T-Case. If water got in there thru the breathers you'll want to replace the fluids... especially if you live in a climate where that water could freeze and do irreparable damage those units.

 

X2

 

Just out of curiosity, how does one check the fluids for water without draining them?

 

By draining them.

 

you could suck some out through the fill hole. Bu I would just drain the fluid and replace if there was enough suspicion to bother checking. You’re already there anyway.

 

Okay. So please clarify, because it seems that what’s being implied is that a fluid change is prudent whenever the vehicle fords anything deep enough to get the axles wet.

 

Anything over the breather can get the diff wet inside. The breather is directly attached to the top of the rear diff. They aren’t designed to be dunked under water unless you have an extended breather.

Like on my Tacoma, my rear breather is extended and sits behind my driver tail light.

https://www.northridge4x4.com/part/170112-arb-differential-breather-kit

This is the location of the rear breather. Mine of course has a hose because it’s re-routed.

 

That breather is maybe 2 to 3 inches higher than the center of the wheelhub. Which is pretty close to the bottom of the body. If you go that deep, you’d be safest draining your rear diff.

 

I should add, the breather is supposed to shut, I think in situations where the diff experiences vacuum (like when a hot diff is cooled by water resulting in a vaccuum inside). So it’s not guaranteed that you would suck in water, and turn your diff oil into mayonnaise. But it’s more about safe than sorry, especially since I think that would be exceeding the maximum fording depth of the 4runner.

 

Okay. This mostly lines up with my prior knowledge. My understanding is that the water doesn’t get into the diff through the diff breather. It gets sucked in through the axle seals when a hot axle is suddenly doused with cold water. The purpose of the diff breather is to prevent the vacuum that sucks water in past the axle seals. The diff breather closes when the breather itself is submerged, so that water doesn’t just pour into the diff. I think it takes a long and deep bit of wading to contaminate the gear oil.

 

Oy, Cap'n: I have gotten wetter than many in various crossings, and when I changed my diff oil after multiple dozens of river fords there was no evidence of water contamination. I don't have any breather mods. Personally, I rate this concern of water intrusion to be not a worry... though obviously opinions vary.

https://youtu.be/-fVw9N4T6aI

 

My prior vehicles, a 1985 G-Wagen and a 1997 Defender, both had remote breathers from the factory. So this is the first time I’ve had to really think about it beyond the theoretical.

Nice crossing by the way. I saw that video in another thread, along with a video about plumbing one’s own remote breathers. Interesting that the threads on the stock breathers are BST.

 

yeah, i doubt its common, but it did happen to a guy with his CX5, and the crossing was no more than 7" or 8" deep. obviously different vehicles, but the science behind it happening is still the same, and swapping out the fluid is cheap insurance.

 

I agree that it worth checking, or just changing the differential fluid to be safe.

I'll have to see how mine looks the next time I change it, as I also tend to practice proper driving technique at times. No breather mod... yet.

 

nice!