4x4 high flashing occasionally

[CHAD HEDRICK]

on my 2002 4.6 explorer XLT twice now in 1 month of driving it, the 4x4 high lamp flashes for that drive cycle. I scanned for codes and C1237 came up. so I replaced the rear abs sensor in the diff. but a few weeks later the flashing lamp happened again. it shifts into 4x4 fine so I'm thinking its not the t case shift module. I've read about being maybe 1 of the t case speed sensors maybe. other than the lamp flashing its drives perfect. please note my 4x4 low does not flash only the high lamp. any advice would be wonderful thanks in advance

 

[Exproblems]

on my 2002 4.6 explorer XLT twice now in 1 month of driving it, the 4x4 high lamp flashes for that drive cycle. I scanned for codes and C1237 came up. so I replaced the rear abs sensor in the diff. but a few weeks later the flashing lamp happened again. it shifts into 4x4 fine so I'm thinking its not the t case shift module. I've read about being maybe 1 of the t case speed sensors maybe. other than the lamp flashing its drives perfect. please note my 4x4 low does not flash only the high lamp. any advice would be wonderful thanks in advance

Did the C1237 code come up as the problem for the rear ABS speed sensor mounted on top of the rear diff housing or did you just guess and replace it by chance? Any ABS warning lights flashing along with the 4x4 high light? I am not sure if there is a speed sensor on top of the T-case, don't think so, but there are two ABS speed sensors on the front wheels, one on each hub assembly. 3 speed sensors in total. Never heard of any more than that. Check the front hub bearings for loose play, wouldn't hurt.

 

[CHAD HEDRICK]

just to clarify my abs lamp never came on, but after the first time the 4x4 high lamp flashed on and off while I was driving to work we scanned for codes and it had c1237 stored so for the 40 dollar gamble I replaced the rear ABS sensor on the diff. all my wheel bearings front and rear are perfect as both rear and the pass front have been replaced in the last year. so that also means only the left front abs sensor hasn't been replaced. I also read though there are 2 speed sensors on the t-case not for abs but for measuring the front and rear driveshaft speeds. some people have had luck fixing the issue replacing those from what I've read. 4x4 shifts fine in and out of high and low when the lamp isn't flashing but I will have to try it next time while the 4x4 high lamp flashes.

 

[CHAD HEDRICK]

so it happened again this time I counted the flashing high lamp which flashed 7 times.
4x4 shifted fine though

 

[OUMX117]

Did you ever find a resolution to your issue? My 04 has the same issue currently.