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Grove AT740 Crane Jumps into reverse.

kenjr ยท 2023-08-25 16:19

Crane jumps into reverse when started from the driver cab. Will not go into drive. Works normal when started from operator cab. HELP??

Replies6
  1. #1crane operator2023-08-25 17:00

    You should have a separate FNR keypad upper and lower. So it works right upstairs but not downstairs. So I'm going to shoot a wild guess and say its either the keypad downstairs, or the wiring harness downstairs between the keypad and the transmission. So I personally would swap keypads from upstairs to downstairs, and see if the problem follows the keypad or not. I'm going to guess that its not the keypad and you've got a wiring harness or connecter problem between the keypad and the transmission. But at least you can test and see if the keypad is the problem.

  2. #2kenjr2023-08-25 20:26

    I'm not sure what you mean by keypad. This crane has a shifter 1 to 6 downstairs and 1 to 3 upstairs. its a 1990 model AT 740 B I think you might be talking about a newer crane. Thanks a lot for the reply!!!

  3. #3crane operator2023-08-25 20:38

    The later ones are allison transmissions. Sorry. that's what I thought yours had. I think the early ones are maybe a funk transmission, sorry. Does the lever move a manual push pull cable downstairs, or does it run a electrical pad/ board?

  4. #4kenjr2023-08-25 20:44

    It runs a electrical board.

  5. #5crane operator2023-08-25 20:56

    Time to get out the tester and see what's going on. Process of elimination. You know the problem isn't in the transmission, because it works right upstairs. Something is whacked in the downstairs board, or in the wiring. I'm guessing wiring, but I'm wrong on a daily basis.

  6. #6kenjr2023-08-25 21:23

    I think your right, seems like we got power going to where it shouldn't be, kinda weird... maybe I just don't get something.