P1780 code - trans ctrl switch???
New User
Joined: Sep 2015
Posts: 15
Likes: 0
but u say that the problem in the transmission is that simple process which u siad up here?
New User
Joined: Sep 2015
Posts: 15
Likes: 0
Sorry man i wasn't clear. My expedition 2005 5.4L, the computer show me the code p1780 transmission control switch. The issue in truck is like the presure in the throttle converter doesn't increase, so whenever I push the acelerator, the rpm go up but the truck moves slowly. You can see the rpm go up and the truck moving slow. In conclusion, I would need to know if anyone herad about this prooblem or whether know which would be the problem in order to fix it. Thank you very much.
Posting Guru
Joined: Dec 2014
Posts: 1,792
Likes: 3
Let me see if I can make it more clear. You start it up, engine runs normally and revs normally. Put it in Drive (D) and hit the accelerator and the engine revs, but the truck hardly moves?
Sounds like transmission slipping. Have you checked the transmission fluid? Is it at the correct level and is it bright red and no burnt smell?
When you put it in D, do you feel that the truck goes into gear? (slight drop in engine rpm, and a subtle kick in the truck). Does it reverse normally (try "R")? Is there any difference if you select 1 or 2 rather than D?
Ignore the code P1780, it only shows that the O/D switch wasn't pressed during a test, as Mark already told you. It has nothing to do with the issues you describe.
Sounds like transmission slipping. Have you checked the transmission fluid? Is it at the correct level and is it bright red and no burnt smell?
When you put it in D, do you feel that the truck goes into gear? (slight drop in engine rpm, and a subtle kick in the truck). Does it reverse normally (try "R")? Is there any difference if you select 1 or 2 rather than D?
Ignore the code P1780, it only shows that the O/D switch wasn't pressed during a test, as Mark already told you. It has nothing to do with the issues you describe.
New User
Joined: Sep 2015
Posts: 15
Likes: 0
Let me see if I can make it more clear. You start it up, engine runs normally and revs normally. Put it in Drive (D) and hit the accelerator and the engine revs, but the truck hardly moves?
Sounds like transmission slipping. Have you checked the transmission fluid? Is it at the correct level and is it bright red and no burnt smell?
When you put it in D, do you feel that the truck goes into gear? (slight drop in engine rpm, and a subtle kick in the truck). Does it reverse normally (try "R")? Is there any difference if you select 1 or 2 rather than D?
Ignore the code P1780, it only shows that the O/D switch wasn't pressed during a test, as Mark already told you. It has nothing to do with the issues you describe.
Sounds like transmission slipping. Have you checked the transmission fluid? Is it at the correct level and is it bright red and no burnt smell?
When you put it in D, do you feel that the truck goes into gear? (slight drop in engine rpm, and a subtle kick in the truck). Does it reverse normally (try "R")? Is there any difference if you select 1 or 2 rather than D?
Ignore the code P1780, it only shows that the O/D switch wasn't pressed during a test, as Mark already told you. It has nothing to do with the issues you describe.
Exactly it is like transmission slipping, the fluid is perfect in level and color, my reverse works perfect but no 1 and 2
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Frmr Ford Trans Engr
Joined: Aug 1999
Posts: 24,730
Likes: 2,658
From: SE Florida
My guess from this information is that the trans is stuck in a higher gear, it's not starting in first gear. What happens if you move the shifter to 1 to get started? Is it better?
New User
Joined: Sep 2015
Posts: 15
Likes: 0
drive, first, or second is the same. but I feel when move the handle to first or drive that gear move, like i feel that the truck is un drive or first but still don't move fast, is like as the truck is always in 3
Frmr Ford Trans Engr
Joined: Aug 1999
Posts: 24,730
Likes: 2,658
From: SE Florida
Excellent question! I'm very interested in the answer.