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Unread 03-12-2012, 03:13 PM   #1
BigRedWilkey
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Auto trany

I have a 1990 mj with the auto tranny. It won't shift and if been told that it is the shift control box. Has anyone else ever encountered this problem? And where is the shift control box???

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Unread 03-12-2012, 03:37 PM   #2
BigRedWilkey
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Just got told it was the transmission control module???
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Unread 03-12-2012, 04:01 PM   #3
mj40
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mine was below the glove box like the one in the pic..
trans-module.jpg  
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Unread 03-12-2012, 06:00 PM   #4
BigRedWilkey
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Where can I get a new one ???
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Unread 03-13-2012, 07:29 AM   #5
cruiser54
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Quote:
Originally Posted by BigRedWilkey View Post
Where can I get a new one ???
Wanna try something else first that's cheap and easy?

Right near the TCU, as shown in the above photo, is an inline fuseholder with a fuse in it. Normally wrapped in yellow tape. If that fuse is blown or corroded, that could be your whole problem.
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Unread 03-13-2012, 09:05 AM   #6
BigRedWilkey
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Already looked at the fuse you mentioned and it's good
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Unread 03-13-2012, 03:22 PM   #7
cruiser54
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Quote:
Originally Posted by BigRedWilkey View Post
Already looked at the fuse you mentioned and it's good
Junkyard is the best place. They rarely fail. Get one from an 88 to 90.

Have you checked the connectors under the hood yet?
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Unread 03-13-2012, 05:54 PM   #8
BigRedWilkey
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Which connectors?
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Unread 03-13-2012, 06:01 PM   #9
cruiser54
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Near the trans dipstick tube there are 2 rather large squarish connectors. One is gray and the other black. Those two connectors are the information superhighway between the TCU, trans solenoids, speed sensor, and TPS. Unplug them, clean them out with electical contact cleaner, inspect the pins, add dielectric grease and plug them back together.
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Unread 03-14-2012, 07:45 AM   #10
BigRedWilkey
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Thanks I will try this when I get home and let you know!
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Unread 03-15-2012, 09:20 PM   #11
BigRedWilkey
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Checked the connection today. Very dirty so I cleaned them up and took it for a spin..... Sadly nothing. Any other suggestions?
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Unread 03-15-2012, 09:21 PM   #12
cruiser54
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Quote:
Originally Posted by BigRedWilkey View Post
Checked the connection today. Very dirty so I cleaned them up and took it for a spin..... Sadly nothing. Any other suggestions?
How many connectors did you clean? One or two?
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Unread 03-15-2012, 09:38 PM   #13
Azzy
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Search on here for AW4 Shift Pointers. it will tell you how to test your tps and see if you need to buy one. I know the latter ones run about 80 for used, and 200 for rebuilt.

Also check under your hood at the pdc and see if any of the fuses there are bad. Are your grounds good?
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Unread 03-22-2012, 08:13 AM   #14
BigRedWilkey
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I replaced the TCM last night and it fixed the problem! I had to go to 4 junk yards to find one but I finally did. Thanks to everyone for their time.
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Unread 03-22-2012, 08:23 AM   #15
cruiser54
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Glad to hear it. What year did you get the TCU out of?
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