Hill descent/ascent failure code

I own a 2015 Explorer XLT with almost 173,000 miles, and it’s been great overall. Last night, during heavy rain, the car downshifted very hard going down a hill. At the bottom, the all-terrain lights came on with codes for descent/ascent failure and other terrain mode issues. Today, everything seems fine with no warning lights, especially since it hasn’t rained.

My husband checked with his laptop and found a lot of codes, including some for wheel speed sensors failing, but there were many codes overall. The car drives and runs fine today. Before the codes appeared, I was stopped behind a school bus with the heat on, and the front end of the car would shudder repeatedly until I turned off the heat. It did the same thing for my husband today, and he thinks it might be the compressor engaging and disengaging. I’ve had to replace the compressor five times in the five years I’ve owned the car.

Any ideas on what might be causing these issues? A friend of mine has had similar problems and just drives carefully in heavy rain. I have one year left on my loan and still owe $6,000, so I’d like to keep my car at least until the loan is almost paid off.

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I had similar error messages and other strange issues with my 2019 XLT. After replacing both front wheel ABS sensors, all the errors disappeared.

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He replaced my passenger one like 3 weeks ago, maybe he will need to replace my drivers side one then.

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Had issues with my F150 when the throttle body got really dirty. I found a discussion on another forum where people said that dirty throttle body sensors can cause strange codes, like the hill assist error. I replaced it, and everything was fine afterward. It might be worth checking your throttle body.

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consider looking for a different dealership, they may give you a better opinion

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We thought that too. So far it’s stayed out. :upside_down_face: