Transmission problems

HoosierJeeper · **Joined:** Sun Feb 15, 2009 8:23 am **Posts:** 1218

Since last October I've had an intermittent PO700 code...general transmission fault. Used to be able to disconnect the battery and all would be well for months on end. Performance would not be impacted. Fast forward to this summer...comes on every month or so, and it won't shift beyond 3rd, then when in 3rd and you go to slow down, it restricts you to only 2nd. Still only getting the PO700. Disconnecting the battery doesn't work any more for more than a few minutes. Is it possibly a simple fix like a sensor or a bad filter? Or should I just suck it up and take it in?

Thanks much.

silverkk · **Joined:** Mon Feb 04, 2013 12:27 pm **Posts:** 637

Talk it In

flash7210 · **Posted:** Fri Sep 04, 2015 5:22 am

Not all code scanners can read transmission faults.
All you will get is a p0700.
Needs to be taken to a good transmission shop.

I suspect its the transmission input and output speed sensors but it could be something else.
A good shop will be able to tell you more.

HoosierJeeper · **Joined:** Sun Feb 15, 2009 8:23 am **Posts:** 1218

How hard are those to replace? I need to get it back in service ASAP and if there's a chance I could get those and get them in, maybe I could avoid taking it to a shop. If they don't fix it well at least I tried. :BANANA:

flash7210 · **Posted:** Fri Sep 04, 2015 8:32 am

see here:
http://www.wjjeeps.com/speed_sensors.htm

and here:
http://www.cascadetransmissionparts.com/545rfespeedsensorkit.aspx

HoosierJeeper · **Joined:** Sun Feb 15, 2009 8:23 am **Posts:** 1218

Would that apply to the 42RLE as well?

flash7210 · **Posted:** Fri Sep 04, 2015 9:11 am

Apparently the 42rle only has one speed sensor?
The parts numbers are probably different too.
Sorry, I'm not as familiar with the 42rle.
Either way, CascadeTransmissionParts will have the sensors.

I thought your 05 KJ would have the 545rfe but maybe I'm wrong.

HoosierJeeper · **Joined:** Sun Feb 15, 2009 8:23 am **Posts:** 1218

The CRD ones have the 545, the gas ones have the 42RLE. I just looked up my service manual, looks like the 42 has two...similar setup to the 545.

Leeann · **Joined:** Thu Mar 14, 2013 9:19 pm **Posts:** 523

The 42RLE has two, both on the driver's side. One input one output. Easy to replace.

Do yourself a favor: get Mopar sensors. Ask me how I know :roll:

Found two pics.

Not connected in this one (they're the things with the single, rusty bolts on the right side of the sensor, both sensors above the shift linkage. The one on the left is broken here and was replaced right after the pic).

And connected in this one:

HoosierJeeper · **Joined:** Sun Feb 15, 2009 8:23 am **Posts:** 1218

Got the codes read.
P1684- Battery disconnected (obviously)
P0218- High Temp Operation (checked tranny cooler- caked with mud/bugs- cleaned out and will see how it runs)
P1776- Solenoid Switch Valve Stuck in low reverse- reverse works fine so won't worry about it for now

The High temp one seems to make sense. When it was acting up the mechanical fan was running flat out so something was obviously hot.

Hopefully cleaning that radiator out helps.

HoosierJeeper · **Joined:** Sun Feb 15, 2009 8:23 am **Posts:** 1218

Cleaned out the tranny cooler and the radiator, no luck- got on the highway and it went through all the gears, then got stuck in 3rd then 2nd.

TwoBobsKJ · **Joined:** Fri May 11, 2012 8:03 pm **Posts:** 463

HoosierJeeper wrote:

Cleaned out the tranny cooler and the radiator, no luck- got on the highway and it went through all the gears, then got stuck in 3rd then 2nd.

Hmmmm...

Did you get the codes read at a tranny shop? My local shop dives down into the TCM and is able to read values while the Jeep is being driven. Gives them insight into how the tranny is operating in each gear, including the input speed from the torque converter and final output speed. I haven't had the same symptoms as you so don't know what could be causing the issue - but if the tranny is going into limp mode in 2nd gear then it's protecting itself from catastrophic damage.

A trans shop may need to get intimate with your tranny to diagnose the problem

Bob

HoosierJeeper · **Joined:** Sun Feb 15, 2009 8:23 am **Posts:** 1218

I just took it to the guy I take the LR3 to- he used a Snap On scanner. Not sure if that's suffice.

Transmission problems

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