1989 Cherokee automatic totally stopped working out of the blue .
#1
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Model: Cherokee (XJ)
1989 Cherokee automatic totally stopped working out of the blue .
The linkage is fine its moving the lever on the tranny and fluid looks and smells good . Any help would be great thanks
Last edited by Chris Shute; 06-02-2019 at 03:48 PM. Reason: Add more
#2
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Year: 1998 Classic (I'll get it running soon....) and 02 Grand
Model: Cherokee (XJ)
Engine: 4.0
Sounds electrical, then. You have a fuse somewhere that powers the TCM (Transmission Control Module). Check for that.
Also, you'll find some excellent tips for your model year on www.cruiser54.com. He's a member here, and his site is the Gold Standard for the Renix years.
Also, you'll find some excellent tips for your model year on www.cruiser54.com. He's a member here, and his site is the Gold Standard for the Renix years.
#3
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Yeah, as BlueRidgeMark said sounds electrical. My 89 did that a few years ago. It turned out to be the transmission control unit (TCU). You can unplug it as I did and drive it around starting in 1-2 then changed to 3, then to D around 45.
If everything does fine that way then you know mechanically it is OK. I went to a junk yard and pull3e two TCU's in case it happens again. I keep the spare in my Jeep.
It will not hurt anything by the way to drive it with it unplugged. About 4 years ago, I drove my 94 for months and 89 like that for a couple weeks before because the brake light switch was stuck so it jarred so bad at 45mph I couldn't take it. It controls the locking and unlocking of the torque converter. Unstuck that switch and all was back to normal on both. The 94 is parked now and yes, Cruiser helped me figure out it was the brake light switch back then. Of course that doesn't sound like your issue.
If everything does fine that way then you know mechanically it is OK. I went to a junk yard and pull3e two TCU's in case it happens again. I keep the spare in my Jeep.
It will not hurt anything by the way to drive it with it unplugged. About 4 years ago, I drove my 94 for months and 89 like that for a couple weeks before because the brake light switch was stuck so it jarred so bad at 45mph I couldn't take it. It controls the locking and unlocking of the torque converter. Unstuck that switch and all was back to normal on both. The 94 is parked now and yes, Cruiser helped me figure out it was the brake light switch back then. Of course that doesn't sound like your issue.
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Year: 1989
Model: Comanche (MJ)
Engine: 4.0
There is a fuse wrapped up in the wiring harness near the trans computer, which is located under the passenger side of the dash. If that fuse fails (or is removed for testing), it will try to start out in 4th gear. You should also be able to manually shift with the shifter into 1st. If its starting out in 1st with the shifter in (D), then it may be an issue with Throttle Position Sensor or the transmission output speed sensor. The TPS is notorious for dying after getting hit with a pressure washer, btw. It's rare that it's the trans computer itself.
Location of the trans computer and advice on cleaning the connectors.
http://cruiser54.com/?p=58
Also check the cable from the throttle body to the transmission. If that's detached or way out of adjustment, it'll shift very sluggish or not at all.
Location of the trans computer and advice on cleaning the connectors.
http://cruiser54.com/?p=58
Also check the cable from the throttle body to the transmission. If that's detached or way out of adjustment, it'll shift very sluggish or not at all.
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Model: Cherokee (XJ)
1989 aw4
There is a fuse wrapped up in the wiring harness near the trans computer, which is located under the passenger side of the dash. If that fuse fails (or is removed for testing), it will try to start out in 4th gear. You should also be able to manually shift with the shifter into 1st. If its starting out in 1st with the shifter in (D), then it may be an issue with Throttle Position Sensor or the transmission output speed sensor. The TPS is notorious for dying after getting hit with a pressure washer, btw. It's rare that it's the trans computer itself.
Location of the trans computer and advice on cleaning the connectors.
http://cruiser54.com/?p=58
Also check the cable from the throttle body to the transmission. If that's detached or way out of adjustment, it'll shift very sluggish or not at all.
Location of the trans computer and advice on cleaning the connectors.
http://cruiser54.com/?p=58
Also check the cable from the throttle body to the transmission. If that's detached or way out of adjustment, it'll shift very sluggish or not at all.
#7
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Year: 1989
Model: Comanche (MJ)
Engine: 4.0
Doing absolutely nothing would definitely be mechanical. Reverse is totally mechanical with no electronics or solenoids involved. I'm thinking pump failed or perhaps you managed to sheer all the torque converter to flexplate bolts. Or maybe something more head slapping like the xfer case is in neutral?
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#8
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Transfer case in neutral?
#11
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Year: 1990
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