Overdrive light flashing
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Overdrive light flashing
Hello all. I have a 93' F250 s/c 4x4 that shifts hard into 2nd and 3rd and the overdrive light has been flashing ever since I bought this truck back in Oct. Any suggestions? It is a low mileage 7.3
Lead Driver
Joined: Feb 2002
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From: Greater Austin, Texas
If the light is on and the trans is bang-shifting, the trans is in "limp-home" mode. This will eventually wreck the trans if used this way long-term.
The first thing I would do is reset the computer by disconnecting the battery for about 10 minutes. If the condition comes back, then you will need to check the error code(s) to see what is the matter. I had that exact truck a few years back with the same issue and the problem was the lock-up clutch in the TC had failed.
The first thing I would do is reset the computer by disconnecting the battery for about 10 minutes. If the condition comes back, then you will need to check the error code(s) to see what is the matter. I had that exact truck a few years back with the same issue and the problem was the lock-up clutch in the TC had failed.
Fleet Owner
Joined: Oct 2005
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From: Kentucky
I would advise to read the codes before clearing them. Since this is a diesel I am not certain if a standard code reader can read transmission codes. I recall other conversations where only a Ford reader can do this on IDI trucks. Could be wrong....
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From: Central Mississippi
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Cargo Master
Joined: Mar 2007
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From: Arcadia, Fla
As your speedo(PSOM) "appears" to be working, it may not be sending out the speed signal properly to the ECU(engine and transmission controller)
Here is a good thread on the OD light flashing. Please read , lot of good diagnostic info. On post #14, I outlined how the PSOM operates and issues with them.
https://www.ford-trucks.com/forums/1...off-light.html
By the way, my E350 is again doing the exact same thing like your truck. Another PSOM rebuild for me and hope to get all the acid from the PCB.....
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From: Central Mississippi
Don't know if the owners manual has survived, but if it has, go through the fuse listing & check every single one that make a reference to anything having to do with the trans and/or speed control etc.
Also if you do get something to read the codes, just because there aren't any doesn't MEAN that there isn't anything electrically wrong. Not that these things are necessarily bad, just nobody ever expected these things to live this long & all manner of weird issues are beginning to crop up.
I would just look at the VSS in the rear. When the bearings get loose, sometimes the tone ring chews into the sensor. Sometimes the magnet in the sensor gets a build up of iron particles on it & weird stuff happens.
Also have a look at the main harness that plugs into the solenoid pack. Its on the pass side to the rear & above the pan. It has a small metal shield held by two bolts & should be stamped "Do Not Remove" Unplug & have a look at the wires going into the plug & look to see if any pins are backing out.
And just for sheets & giggles, is the bed illumination light working/busted out?
Also if you do get something to read the codes, just because there aren't any doesn't MEAN that there isn't anything electrically wrong. Not that these things are necessarily bad, just nobody ever expected these things to live this long & all manner of weird issues are beginning to crop up.
I would just look at the VSS in the rear. When the bearings get loose, sometimes the tone ring chews into the sensor. Sometimes the magnet in the sensor gets a build up of iron particles on it & weird stuff happens.
Also have a look at the main harness that plugs into the solenoid pack. Its on the pass side to the rear & above the pan. It has a small metal shield held by two bolts & should be stamped "Do Not Remove" Unplug & have a look at the wires going into the plug & look to see if any pins are backing out.
And just for sheets & giggles, is the bed illumination light working/busted out?
Cargo Master
Joined: Mar 2007
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From: Arcadia, Fla
If the the OD light is flashing, there is going to be a stored code for the E4OD transmission. I just pulled my usual code 452, which is insufficient input from VSS on my E350 last night.
One other thing to check, does your truck have speed control? If it does, try it and see if it works, if it does but will not hold speed(surges or cuts out), then it is most likely the PSOM. I use speed control on all my trucks and I thought I felt some surging the other day right before the OD light started blinking and the hard shifts came about.
One other thing to check, does your truck have speed control? If it does, try it and see if it works, if it does but will not hold speed(surges or cuts out), then it is most likely the PSOM. I use speed control on all my trucks and I thought I felt some surging the other day right before the OD light started blinking and the hard shifts came about.
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Finally got a scanner - snap on MT2500 to read these codes. 23-fuel injector pump lever out of range, 43-throttle position below idle and 65-overdrive cancel sw-no state change.
Dont really know what these mean but am reading a lot about them now.
Still trying to figure out this snap on to make sure I'm using it correctly lol
Dont really know what these mean but am reading a lot about them now.
Still trying to figure out this snap on to make sure I'm using it correctly lol
