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  Topic Review (Newest First)
01-04-2015 12:24 PM
dechkab It works!!!

The TC WILL NOT LOCK with above circuit operating. Soon as the circuit is turned off the TC locks.
When time permits I will draw the schematic, it is a real simple set up.

I do feel a 555 timer would be the best set up and I do plan to try one at a later time.
01-01-2015 07:56 AM
dechkab Will Do!

I'm going to try an simple electronic style 3 pin signal light flasher and a relay first.
Wire it so the ISO relay load circuit is normally in the closed position.
In theory when the signal flasher is energized it will pulse off-on-off-on at the ISO load circuit mocking what I was doing manually.
This will also put the TC circuit on when the signal flasher is not energized for highway driving.
I'll have to find a flasher that works regardless of load for this to work.
12-31-2014 09:36 PM
Rubi4MyMrs That is an interesting idea. I did work with a 555 in a circuit many yrs ago on some project but remember little about it. It should work as you describe though. Be sure to post results & maybe the circuit when you get it done & working.
12-31-2014 07:43 PM
I have set up the White and Pink wire with a switch to deactivate the TC and it does work but only for about 20 seconds. As it is explained in the link that Rubi4MyMrs provided...Thanks again!

Now I tried manually pulsing the switch on and off every 5-10 seconds, this keeps the TC unlocked. I drove quite a distance doing this and the TC never locked until I stopped pulsing the switch.

So I believe this could be set up with a 555 timer to do the automatically.

I have never worked with a 555 timer before but if one is set up in an Astable Circuit configuration to pulse on/ off every 5 seconds, this should work!
12-28-2014 12:28 PM
dechkab Well I haven't gone any further with the TC at the moment but did do the mod so the Jeep defaults to OD off.

This works great and the Jeep is much happier out of OD, even at highway speeds.
12-16-2014 10:22 AM
dechkab Interesting info...thanks again!

Tonight I'm going to study that thread closer and maybe attempted trying this. Now if there was away to keep the TCC defeated all the time....
12-15-2014 10:25 PM
Rubi4MyMrs I read through the 1st link because I was looking for something I had posted about using the brake switch. I found it in post #35. Then in post #40 it looks like the brake may only holds the lock up off for 30 seconds or so. Then in post #52 he confirms that it works (!) in 3rd & 4th (o/d) but only for 20 seconds, he says.

Which wire to use is described in there along the way. He has a 2003 like you so it should work for you too.
12-15-2014 07:28 PM
dechkab Interesting and clever idea about the OD.

I did s similar thing on my Crown Victoria so the car would default to OD off when starting the vehicle.

I used a momentary push button switch that's defaulted in the closed position and connected the two OD switch wires to it. Worked great other than the push button switch became the OD control instead of the factory button.

I too was thinking about the brake light switch. I tried putting the hazard lights on while driving and the TC did not unlock but did when the brake pedal is depressed.

This leads me to believe one of the other wires going to the Brake Light switch controls the TC. If I can figure out which wire, test the polarity to see if it needs a 12V source or a ground to trick it into unlocking.

Whatever the case I will post any results I come up with.
12-15-2014 06:39 PM
Rubi4MyMrs OK, yes it probably can be done but figuring it out may be a challenge. Here are 2 links, 1 that deals with the o/d automatically turning off which you may like if you always turn it off. The other is about unlocking the TC in o/d which is not what you want but it is a few pages & I haven’t read through it recently so may have info that will help you like if it unlocks when you hit the brakes maybe you can put a switch in there to fool the TC without actually having the brake lights on, not sure. If you do decide to try this & get it to work be sure to post results. I’m sure others would be interested.

Also you might be able to figure it out from the info in the FSM Trans chapter (21) starting at about page166.
12-15-2014 05:49 PM
dechkab Hi

No problems with the auto.
I was attempting to override the PCM in regards to the TC.
I drive with the OD turned off when in town, this causes the TC on constantly lock while driving in town. I wanted to place a toggle switch on the control wire do disable the TC until needed. I realize this will produce an error code.

I have done this in the past on Ford vehicles with no ill effects other than an error code.
After studying some of the diagrams from the link you provided(Thank you very much,very informative)this won't be easily done so I'm not going to bother.

12-15-2014 04:58 PM
Rubi4MyMrs What problems are you having with your auto?

If you have a 2003 with auto you should have a 42RLE which doesn’t have a TCC control. Or at least it is not called that.

The 2002 & earlier had the 30/32RH which used a TCC control & that control wire was C-2, pin 11 in the PCM. Are you using a Haynes or Chilton manual? If so they cause more problems than they solve by trying to cover all yrs with very general info. Get a FSM or use this link.

See online read only FSMs here:
You may have to go to the bottom of the page & pick Jeep Resources & online manuals if it directs you to home page rather than the knowledge base.
Pick your model & year then on the drop down menu pick the chapter you need.
12-15-2014 04:13 PM
2003 Wrangler PCM/Auto Trans Wiring

Hello All

After much searching and can not find accurate transmission wiring diagrams for my 2003 Wrangler 4.0L Auto, does anybody have any 2003 year specific
PCM automatic transmission diagrams they would be willing to post?

I am trying to locate the TCC control wire and any info I have found thus far states it is located at pin11 in the white pcm connector (C2).

Best I can tell there are no transmission wires located in this plug on my 2003. Definitely no wire located at pin 11.

Any help would be greatly appreciated.


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