transmission stuck in Limp Mode (safe mode)

[matemk]

my 92 rodeo is stuck in limp mode. if i put it into D,3, or 2 it doesnt want to go anywhere unless i slam on the gas and even then it bearly go es anywhere. but if i put it into L it takes off like it is supposed to. i have just had a Tranny fluid, filter, and gasket change. i took it to aamco to be looked at and they could not pull codes out of it but they did notice that the wiring harness that goes from the left of the engine bay to the tranny(goes to 3 sensors on the transmission) was laying against the headers and burnt up the protecting cover around it and slightly messed up the wires but no bare wire is showing except the insulated ground wire(im guessing) which is cracked in one place. i am wondering if that could be the cause of it. also at the end of that harness are 2 connectors that dont seem to go anywhere(located at the very back of the transmission on the top, where it meets the drive shaft) they fit into each other but when i took it off they wernt connected, i was also wondering if that could be part of the problem. the winter mode button does not light up on the dash but the power mode button does. this car is confusing the crap outta me and neither me, aamco, or A+ transmission could figure it out, anyone have any ideas?

[doommarine44]

I have a 95 rodeo doing the same thing, its in safe/limp mode, and the check trans light is on.. is your check trans light on? My winter light also does not work.. we have the same issue, and I agree it is annoying the heck out of me.. i took mine to aamco they had no clue either.. I also took it to the isuzu stealer, nada... they were idiots there..
(im a used car dealer got burned on this one )

If ANYONE knows what this could be please enlighten us both..

[matemk]

when i took it to aamco they could not figure out anything but the wiring harness is bad, the one in the dash and from the engine bay to tranny. but when i took it to the isuzu dealership they actually pulled a code out of it, 82 and all they told me was "bad transmission", not very helpful. i ended up taking the wiring harness that goes to the tranny out and replaced a foot and a half of wire and put it back in but it made no difference. then i thought maybe the winter mode button didnt work so i hard wired the switch to see if it did anything but still nothing. i have run out of ideas on what to do except pull each sensor out, clean them and check and see if they are working or not but im not sure if that would make a big differece. the Check Tranny Light is on and flashing along with the Check Engine Light. really confusing and ive had it for about 3 months now and i just wanted to run so i can get it inspected and drive it but still no luck, please anyone who has had a similar experience, anyone who is having the same kind of problem or something similar let us know what you have tried, what worked what didnt work, any idea on which way to go.... any info at all

thanks

[matemk]

ok i have made some progress on my rodeo. today i ripped everything out of the car, i mean everything. i took out all the panels, carpet, seats, even the dash and part of the AC tubing. after looking at some stuff, disconnecting some connectors, connecting them back and all that fun junk to see if anything changes, i plugged the dash lights back in(with the Power mode, winter mode, and check tranny lights on it) started the car and the check transmission light went off. put it into drive and it took off like it was supposed to. woohoo. but then i started trying to find the short in the wires and in the process of doing that i hit something that made the light go back on and the tranny back into safe mode. did some more feeling around on the wires, wiggling wires and what not here and there and the light went off and it came out of safe mode. the i bearly touched the CPU and the light came back on and i have yet to be able to get it back off. So now i believe that my problem lies within the wiring harness to the Main CPU. i am greatly relieved that i dont have to rebuild the tranny.

[doommarine44]

sounds exactly like mine..... where is this cpu and what panels did you remove to get to it easily? I would attempt what you have but im kinda lost on rodeos...

perhaps you could take pictures if you have a digital cam? or just describe the locations?

Thanks alot.. glad to see you have found the issue !!!!

[matemk]

well i played around with it some more last night and found out that it really doesnt have anything to do with the ECU. i found out that if i take the fuse box under the dash and twist it a little bit in a certain direction i can get a cliking noise from the right side of the car under the dash, havent been able to pinpoint where it is clicking from, but i removed the rr def fuse and the clicking stopped and the light went off. there is also a white connector on the right side of the car up under the dash through the passengers vent that if you take it off the light will come on, but when you plug it back in and turn the car off then back on the light turns off. i have reassembled the dash and with luck the light has stayed off. maybe there is a short in the rr def system? not sure but if the light is going to stay off then im going to leave the fuse out

[matemk]

ok this just keeps getting more confusing by the day. i have mananged to get the tranny out of limp mode for good, hopefully. but now i dont have Power Windows(had to take the fuse out to help with the tranny light), RR DEF/Door Locks(had to take that fuse out too), A/C ??? some how i lost the ability to turn on the A/C, and only the far left light on my dash lights work so i can see up to the 3 on RPMS and everything else isnt light. anyone know if all of these are connected in one way???

[doommarine44]

I found out a fix for it, I took it to a SMART mechanic, instead of the 6 other retards that looked at it.. including AAMCO transmissions, as well as the Isuzu stealership (they said they don't pull diagnostic codes so I got the vehicle asap.) it was simply the transmission wiring harness was on the exhaust manifold, burn up pretty good. Got that re-wired now it works perfect!!! Check that wiring harness..

[matemk]

Originally Posted by doommarine44

I found out a fix for it, I took it to a SMART mechanic, instead of the 6 other retards that looked at it.. including AAMCO transmissions, as well as the Isuzu stealership (they said they don't pull diagnostic codes so I got the vehicle asap.) it was simply the transmission wiring harness was on the exhaust manifold, burn up pretty good. Got that re-wired now it works perfect!!! Check that wiring harness..

already tried that, mine was the same way except all i did was replace about a foot and a half of it from the area around the exhaust manifold, it seems to have made a difference in it but occasionally it still goes into limp mode, i have found out though to get it out of limp mode i have to start the car, insert the power window fuse, turn the car off, turn it back on, remove the fuse, turn the car back off, then turn it back on, 99% of the time it works. i am thinking that something is wrong with the fuse box cause if u take out the fuse above it(TCM FUSE) it goes into limp mode, so maybe there is a connection wrong or a loose wire or something i dunno, but i might take the wiring harness back off and go from the beginning to each sensor with new wire and see if that fixes it for good

[doommarine44]

Sorry to hear that, that truely SUCKS... hope you can locate it..... I know what a pain wiring can be... I'm sooooooo glad I got mine fixed.... I thought I had a $2,300 paper weight lol...

[trooperbc]

boy, you sure are patient in dealing with this.

Originally Posted by matemk

already tried that, mine was the same way except all i did was replace about a foot and a half of it from the area around the exhaust manifold, it seems to have made a difference in it but occasionally it still goes into limp mode,.....

you should know that the wiring can be fried further along, and 'buried' within the harness.

but if you still want to try to track this down piecemeal, i'd try first making sure all grounds are good.



good luck

[mobley989]

ok, i replaced my trans with a newer one, and the first one would slip like a mofo. and then just give out, wont go anywhere. then replaced it and now it seems like it is stuck in winter mode or maybe the exhaust is plugged or somethin to do with the limp home mode or the transmission control module, or the throttle body. im getting it checked out. how do you reset the comp for the trans and how do you tel if the tcm is bad? or how do you get it out of limp home mode or the winter mode??????

[bbohica]

The 'limp' mode happened to me a few years ago on my 2000. There is a position sensor on the top of the transmission, I got access to it through the 4WD boot from the interior. Make sure this is connected properly. What are your CEL codes telling you?

[Captain93728]

Hi guys... I have a 95 2wd Rodeo with 152K miles, no major repairs so far. I had the Check Trans Light flashing, clicking coming from under the passenger side dashboard, my door locks were going on and off up and down (mostly close to idle speed), my A/C stopped cooling, and the engine started overheating and would die at idle (not all the time). The idle speed started going up and down between 2500 and 600 rpms and the transmission was stuck in limp mode and would hardly get moving until I put it into Low.

I just happened to look at the charge indicator and saw that it was pegged to over 16volts. I had the alternator tested and it was indeed putting out an OVERVOLTAGE. The Trans Computer, my door locks and my A/C couldn't handle the higher voltage! I replaced the alternator and all is well except I blew a tail light and a head light when the overvoltage happened. Rodeo is running like it always has since I bought it in 95. Hope this helps in some small way.

Cap