not shifting into3rd gear
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not shifting into3rd gear
I have a 99 F-250, V-10 Automatic trans, recently the shifter on the steering column broke, it has been hard to shift from park to drive and so on for some time, I figured it was the cable, after removing to column I replaced the broken piece in the column, traced the problem to the "transmission range switch" , removed this switch and it shifts effortlessly, I don't have the $80 to replace it at this time, so I figured I could set the switch to the "neutral" position and tyrap it to the side of the trans to get me by until I get the $ to replaced it, Heres the problem: the trans wont shift out of 2nd even though its in drive, I did mess with the linkage at the trans, so I don't know if the problem is the linkage adjustment or if the computer needs to "see" the switch change frompark to drive. Any help would be greatly helpfull, Andy
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Joined: Sep 2006
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.....You can't fool the PCM by doing what you are wanting to try.
.....The PCM looks for signals through the DTR to "calculate" in a 3 bit code to indicate what gear was selected.
.....For example a 1-0-0 = gear 1. A 0-1-0 = gear 2. A 1-1-0 = gear 3 etc. .....This is a binary or Octal counting method, witch ever way you want to read it.
.....The reason is the trans is electrically shifted with solenoid valves.
.....The PCM has to know what solenoids to open and close per acceleration and decelleration conditions per speed and throttle position from these coded numbers. Also the program uses different program lines of code for accelleration and decelleration. Reason is to prevent gear hunting up and down.
.....The only mechanical shifting that is done non electrically, is reverse where there is no advantage to electric control so saves production costs and additional complexity, since there is no real acceleration that has to cause a gear change at some point.
Hope this helps you understand why.
Good luck.
.....The PCM looks for signals through the DTR to "calculate" in a 3 bit code to indicate what gear was selected.
.....For example a 1-0-0 = gear 1. A 0-1-0 = gear 2. A 1-1-0 = gear 3 etc. .....This is a binary or Octal counting method, witch ever way you want to read it.
.....The reason is the trans is electrically shifted with solenoid valves.
.....The PCM has to know what solenoids to open and close per acceleration and decelleration conditions per speed and throttle position from these coded numbers. Also the program uses different program lines of code for accelleration and decelleration. Reason is to prevent gear hunting up and down.
.....The only mechanical shifting that is done non electrically, is reverse where there is no advantage to electric control so saves production costs and additional complexity, since there is no real acceleration that has to cause a gear change at some point.
Hope this helps you understand why.
Good luck.
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