4X4 Electric Shift Motor Fix Guide
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From: San Diego
4X4 Electric Shift Motor Fix Guide
This guide is for a Explorer/Ranger transfer case problem..Is there something like that for the F150 electric shift motor in order to fix my broken motor or detect if really is the electric shift motor the real problem.Electric Shift Motor Guide
I have the detailed repair bible out in front of me, wherein the cover for the position sensor assembly is not shown as a separate part. So, there's no removal/replacement procedure detailed, and no method for alignment described.
IF IT WAS MY CAR-- I'd be working with the manuals and the switches and the good old ohmmeter to get all this stuff lined up again. The first task is to get the shift motor to some known position. The easiest is probably to the 2WD position. The manual then gives a matrix of switch positions vs. motor positions to go through. Using the ohmmeter on the terminals of the eight-pin harness connector at the shift motor, look for the following conditions. Do this testing on the connector terminals of the transfer case with the harness disconnected.
In 2WD position, pin 10 (yel/wht, circuit 762) should show continuity with pin 6 (violet, circuit 771) and continuity with pin 8 (brn/wht, circuit 764), and should show no continuity with pin 7 (white, circuit 770) and no continuity with pin 9 (org/wht, circuit 763)
In the 4WD/Low position, pin 10 (yel/wht, circuit 762) should show continuity with pin 6 (violet, circuit 771) and continuity with pin 7 (white, circuit 770), and show no continuity with pin 8 (brn/wht, circuit 764), and no continuity with pin 9 (org/wht, circuit 763)
These descriptions cover the two extreme positions in the rotation of the transfer case shift motor. To move the transfer case motor, apply 12V to the following terminals: +12V to pin 3, (yellow, circuit 777) with -12V (ground) to pin 2 (org, circuit 778). Reverse the polarity of these connections to rotate the motor to the 4WD/Low position. Again, make this connection to the shift motor connector with the harness disconnectIed. IT IS EXTREMELY IMPORTANT THAT YOU MAKE EXACTLY THE CORRECT CONNECTIONS WHEN YOU DO THIS. ACCIDENTALLY SHORTING THROUGH ONE OF THE SWITCH CONTACTS OR THE SPEED SENSOR WITH 12 VOLTS WILL DESTROY THEM.
The color codes on the harness wires provide the best identification of the correct circuits. This connector is a square plastic outside shell with a round barrel inside, and a circular ten-pin array, pin one is in the center. Looking at the motor connector from the control wiring harness end, the pins are numbered as follows:
(Very bad html version of ASCII art follows)
3 2
4 10
5 1 9
6 8
7
|-- --|
It appears from the manual drawing that those two key slots in the motor connector are opposed at the bottom as shown in the above diagram; you should still confirm the harness color codes before applying any voltage to shift the motor. Also remember that the transmission needs to be in neutral when you do the shift. Keep the 12V power attached only for the time needed to shift the case-- maybe 5 seconds max.
Once you've forced the motor to the extremes of its travel, you can install the cover and position sensor assembly in whatever position you need to get the switch logic detailed above. This may take a bit of time and patience, but is still cheaper than a few hundred bucks spent replacing the whole motor/sensor assembly.
Should the problem ever arise again with the motor slipping out of position, the best way to get it back is probably to just apply the 12V to the motor leads as detailed above, until it returns to the 2WD position. If the controller is still confused, disconnect the battery for a minute or two so the controller can "forget" that it doesn't know where the motor is.
Contributed by Alfredo C.
My Explorer remains in 4x2, and nothing happened when I tried 4x4 or Low Range buttons. I did all the tests described in the article, and I concluded that the problem was the transfer case sensor.
I took apart the whole case. I verified that the white wheel with the printed circuit (photo 1) had been unstuck from the central axis. I solved this problem with some dots of Loctite.
PHOTO #1
Additionally, I am sending another photo of a transfer case without the electronic engine showing the indicators of 4H, 4L, and 2H positions.
PHOTO #2
Please send me any information like that for a 1997 F-150 with 4X4 problem
I have the detailed repair bible out in front of me, wherein the cover for the position sensor assembly is not shown as a separate part. So, there's no removal/replacement procedure detailed, and no method for alignment described.
IF IT WAS MY CAR-- I'd be working with the manuals and the switches and the good old ohmmeter to get all this stuff lined up again. The first task is to get the shift motor to some known position. The easiest is probably to the 2WD position. The manual then gives a matrix of switch positions vs. motor positions to go through. Using the ohmmeter on the terminals of the eight-pin harness connector at the shift motor, look for the following conditions. Do this testing on the connector terminals of the transfer case with the harness disconnected.
In 2WD position, pin 10 (yel/wht, circuit 762) should show continuity with pin 6 (violet, circuit 771) and continuity with pin 8 (brn/wht, circuit 764), and should show no continuity with pin 7 (white, circuit 770) and no continuity with pin 9 (org/wht, circuit 763)
In the 4WD/Low position, pin 10 (yel/wht, circuit 762) should show continuity with pin 6 (violet, circuit 771) and continuity with pin 7 (white, circuit 770), and show no continuity with pin 8 (brn/wht, circuit 764), and no continuity with pin 9 (org/wht, circuit 763)
These descriptions cover the two extreme positions in the rotation of the transfer case shift motor. To move the transfer case motor, apply 12V to the following terminals: +12V to pin 3, (yellow, circuit 777) with -12V (ground) to pin 2 (org, circuit 778). Reverse the polarity of these connections to rotate the motor to the 4WD/Low position. Again, make this connection to the shift motor connector with the harness disconnectIed. IT IS EXTREMELY IMPORTANT THAT YOU MAKE EXACTLY THE CORRECT CONNECTIONS WHEN YOU DO THIS. ACCIDENTALLY SHORTING THROUGH ONE OF THE SWITCH CONTACTS OR THE SPEED SENSOR WITH 12 VOLTS WILL DESTROY THEM.
The color codes on the harness wires provide the best identification of the correct circuits. This connector is a square plastic outside shell with a round barrel inside, and a circular ten-pin array, pin one is in the center. Looking at the motor connector from the control wiring harness end, the pins are numbered as follows:
(Very bad html version of ASCII art follows)
3 2
4 10
5 1 9
6 8
7
|-- --|
It appears from the manual drawing that those two key slots in the motor connector are opposed at the bottom as shown in the above diagram; you should still confirm the harness color codes before applying any voltage to shift the motor. Also remember that the transmission needs to be in neutral when you do the shift. Keep the 12V power attached only for the time needed to shift the case-- maybe 5 seconds max.
Once you've forced the motor to the extremes of its travel, you can install the cover and position sensor assembly in whatever position you need to get the switch logic detailed above. This may take a bit of time and patience, but is still cheaper than a few hundred bucks spent replacing the whole motor/sensor assembly.
Should the problem ever arise again with the motor slipping out of position, the best way to get it back is probably to just apply the 12V to the motor leads as detailed above, until it returns to the 2WD position. If the controller is still confused, disconnect the battery for a minute or two so the controller can "forget" that it doesn't know where the motor is.
Contributed by Alfredo C.
My Explorer remains in 4x2, and nothing happened when I tried 4x4 or Low Range buttons. I did all the tests described in the article, and I concluded that the problem was the transfer case sensor.
I took apart the whole case. I verified that the white wheel with the printed circuit (photo 1) had been unstuck from the central axis. I solved this problem with some dots of Loctite.
PHOTO #1
Additionally, I am sending another photo of a transfer case without the electronic engine showing the indicators of 4H, 4L, and 2H positions.
PHOTO #2
Please send me any information like that for a 1997 F-150 with 4X4 problem
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From: San Diego
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Electronic shift
I have a 97 F-150 but my fix may apply--After reading several post after my 4x4 would not shift I removed the shift motor, cleaned the armature and inspected it, reinstalled it and it still would not work. I could not hear any clicking of the relays nor would the indicator lights work. Today while returning from work at the church I was thinking about what I could check when getting home. I wondered if removing the battery cable and letting the computer reset--what do you know it worked, something very simple.