shade2000

Hello everybody,

A new member here, my name is Faisal and i am from the UAE. I have a 2000 Cherokee with automatic transmission and it’s been giving me some troubles for a long time. I ate through all the posts here and finally decided to write one hoping to get some answers. Mechanics here in the UAE are not very capable when it comes to diagnosing anything, so this would be my last resort.

For quite sometime, my overdrive has been giving me troubles, some times it would be okay, sometimes it wont, i’ll put the car in neutral and back to drive and it would solve it. But eventually i changed the whole transmission with another used one (we dont get new parts here for the XJ easily) because my old transmission would leak all the time too because of a few slipped bolts.

New Transmission in, cleaned the NSS, new fluid (Dex III), for a bit overdrive worked, then back to the same issue. Also my Idle RPMS and even when i am in drive sitting on a red light, my rpm would want to jump up and up. Read here that TPS might be a culprit, changed the TPS, a little bit of betterment in RPM but still no overdrive.

Some more research and read that cleaning your grounds may help, up until this point, car shifts in all gears except OD, took it to mechanic, cleaned up all the ground connections, started the car to drive back home. In “D” it would take off, shifts to 2nd and when its supposed to shift in 3rd, it wont, just revs up. Like it went into neutral.

Had some codes about Stuck solenoids A & B, torque converter lockup stuck, and pedal/position sense voltage low (Afterwards i changed the TPS).

I did order new solenoids as it takes a lot of time but is there something obvious i should check? does it sound like an electrical problem or something mechanical? As i mentioned, if i give my cherokee to my electrician for diagnosis, then i am dead. I am writing this because how come solenoids are bad in my old AND in the new transmission, maybe something is wrong somewhere else. and how come right after cleaning the ground connections, i lose 3rd & 4th as right before that it was okay. Just no OD.

Your help would be really really appreciated. I am not a newbie to car stuff but i have NO CLUE when it comes to checking electrics. So i request you to please be easy on me.

Thank you.

awg

quick answer

you absolutely must free download the Factory service manual

If you dont do that, and read the relevant sections, you will probably not be able to diagnose the problem, so I assume you already have done that ?

the overdrive solenoid engagement is problematic for many people, including myself

There is several factors involved, including the brake switch (will cause OD to disengage)

In addition the wire harness that leads to the solenoids is "delicate" and can give intermittent (or permanent) high resistance

These faults must be checked systematically using the info in the service manual to guide you

each solenoid should be ~14 Ohms when measured between battery negative and the appropriate cavity in the connector alongside the RH engine

Unfortunately you have to systematically go through each of the tests outlined in the manual

An auto electrician would only do the same, (needing to use the manual), but charge you hundreds of $

You may be able to find details of what I have mentioned by searching previous posts

It is not hard to do, you do need a multimeter.

It is essential to have some grasp of auto electronics when working with older vehicles

Ricthewrench

Factory manual for the win, absolutely the right move. Testing is much easier than spending all your money on parts that may or may not need replacing.

cruiser54

Just for fun, clean the connectors per www.cruiser54.com. Post 10.

I would also look around the brake light switch at the pedal.

shade2000

.

shade2000

I did try cleaning. No change. What exactly i am looking at the brake pedal?

shade2000

Thank you for responding and getting me these helpful tips. Yes out of depression i did download the manual but as i sad with electronics i am really really bad so i didn't understand much. But your suggestion about wire harness, i did give it a go and checked with a multimeter. Not the readings i expected but could be that i am using the tool wrong. I read it somewhere else in this forum how to test and applied.

I had the black wire onto the battery positive and red wire into the female connector. In my car the grey one had like 6 or 8 connector so no "a row with 4 pins" but the black one is like that. I checked both, for some reason i am not getting the ohms reading in two digits. I have set my multimeter to the lowes ohms resistance which was 200. sometimes no change in numbers, sometimes they jump to random 3 digits number (like 689, 741) and back to .1

Does this tell you something? So sorry about this weird result. I was hoping to get straight ohms reading. Also i wasnt sure so i did try with both ignition on and off but couldn't get any stable 2 digit reading.

awg

It is "suggestive"

Examine the wire colors to ascertain the ones the solenoids, there will be three. You need to identify this from the relevant circuit diagram or page.

Identify the overdrive solenoid cavity and probe that

with the setting on 200 ohms it will read around 14 ohms..it will be expressed 3 figures, like 14.2. If it is much over that, their may be a problem

Using a multimeter, the reading can jump around, especially low ohms, as the leads dont make perfect contact

black lead should go to battery neg terminal, or ground, red to probe cavity

furthermore, with the harness disconnected, you should be able to stimulate the solenoid to click by applying 12V to the appropriate cavity pin

the OD solenoid is different from the other two, and makes a pretty quiet click, you may not here it in the pan

If the steady resistance is over 14 ohms, it indicates a problem with wiring or solenoid

Ricthewrench

Solenoids are likely suspects. Start testing! A little time spent learning how to test & what your results mean will forever pay you back. I start at the item(solenoid in your case), test that. Then go up the circuit wiring & connectors. All good, next item. 👌

shade2000

Feels like that 8 pin connector is the culprit. I dont know how I didn’t notice it before but it seems fried with wires tangling with each other.

i will try and fix these wires as i have no hope in finding this connector anywhere.

can this be the end of my nightmares?


This is the 8 pin connector next to dipstick where the wires from the trans connect.

cruiser54

See Post #4. Had you not ignored or overlooked it, your problem woulda been found right off the bat.

awg

Not to panic, just get a pack of insulated male & female spades, snip the harness, crimp the spades on the wires good and tight

Obviously when doing this, one must take extra care to make sure that wires don't get mixed up

It is best to use the "Pin Out" and or circuit diagram to make sure, as the in/out wires colors don't always match

I will allow you exactly one guess on how I know this

Once you have completed the rewiring, verify it is correct by testing solenoid resistances etc

shade2000

Thank you. I literally re-checked because of your comment. Just in hopes of finding something

shade2000

FIXED!
Did exactly that, repaired all the wires one by one. Everything worked for a few minutes but again OD problems and goes to neutral instead of 3rd gear. I was due on my last "drain & fill" and the pan was down. So i replaced all 3 solenoids and it now shifts like a dream and OD is back. I scanned the car after fixing wires and under TCU, it said "Solenoid C shorted due to voltage". Maybe because of that wiring mush, toasted the solenoids. Thank you so much for your help really.

A few more things that remains and i would love to ask your help with those but i decided to post a new thread so this one remains clean for other people to get help from your inputs.
this is the link to the other post, i would love your help on this.

Thank you so much!