ADJUSTING THE SELECT LEVER CONTROL CABLE AND SHIFT ROD
Shift rod:
a. Make sure that the select lever and transmission are in HIGH.
b. Loosen both locknuts 1.
c. Adjust the length a of the shift rod to 413 mm (16.3 in).
d. Tighten the locknuts.
e. Start the engine, and then check that the select lever can be shifted to each shift position
and that the appropriate indicator light comes on when the lever is in each position.
f. Adjust the shift control cable again.
Cable6A.jpg
There is also the LOCKOUT mechanism, (shift control cable #6) that prevents shifting into reverse or park UNLESS the REAR BRAKE is applied.
Cable6.jpg
Check the lockout mechanism first, likely it is not pulling back far enough to allow the lever to pass by, and go into Rev or Park.
Good Luck