The only thing so far I have been able to find on Code P1789 is OD/2-4 HYDRAULIC PRESSURE SWITCH CIRCUIT. Which could be just the Selenoid Pack.Ok, the 45 code info I have says to replace the TCM (Tansmission Control Module)
Here are the 2 locations... Depending on Body Style...
FJ22 Body

NS Body

.
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Friday, May 21st, 2021 AT 2:55 PM
(Merged)


