OD off flashing with P0741 code

knl25 · #1 11-28-2007, 08:57 AM

It's a 2000 3.8L with 140K mi. I have the OD off light flashing while on highway. The light is off after the engine is restarted, but usually appears again after 100-200 miles. I have Autoenginuity scantool and got the code P0741 (torque converter clutch circuit performance or stuck off). I also noticed when the light is on the transmission fluid temperature is about 40 degrees higher than when it is not on (190 when on and 150 when off from scantool). The car seems to drive normal. Fluid looks good and at correct level.

I hope this is electronic related problem, like failed sensor, or something like that and not mechanical issue within the transmission since when the engine is reset the light is gone. I also have another code that says something about the ambient temperature sensor is failed within the transmission module that starts with the letter B (Bxxx) that I forgot the exact code, but this one has always been there so I ignore it, and now not sure if this is related.

I hope someone could let me know what the problem is and whether I need to take it to Ford or any mechanics could diagnose this. Thanks.

tomj76 · #2 11-28-2007, 11:33 AM

I recently had a problem with my transmission that showed a problem with the torque converter clutch solenoid. It might have been the same code you're getting.

The problem was real, in the transmission. In my case the transmission was at a point where it needed to be rebuilt. Part of the problem was that due to the failed clutch seloid, the torque converter overheated. The car was at 200k miles when this happened.

You can tell if the clutch is working properly if you watch your RPM's when driving. After the transmission reaches overdrive, the RPM's will drop again when the clutch engages. This can also be observed in drive when the O/D is disabled.

I also had a "chatter" where the clutch would intermittently and spontaneous disengage, and then re-engage. The action would cause the front end to vibrate. It occurred in drive as well as overdrive.

I believe the clutch solenoid can be replaced without removing the transmission.

12Ounce · #3 11-28-2007, 12:15 PM

Yes, I would try the solenoid first ... and it is changeable while in-vehicle. So is the pressure regulator. Good luck.

The increased temp is expected when the clutch isn't engaged. The clutch won't re-engage until the motor is shut off and restarted ... at least, mine is this way,

I've been thru this recently/currently. Getting the same code. Changed everything I could get my hands on ... wasted money in my case. I've decided to change out the tranny myself with Ford part ... and do a engine refreshing at the same time. My '99 has over 200k miles ... so the engine could stand a once-over. Just ordered the engine gaskets moments ago.

knl25 · #4 11-28-2007, 12:22 PM

I should probably try to replace the solenoid then. Do you guys have the part number for it? I tried the online team ford parts website but couldn't locate it. How easy is the swap? Do I need any special tool?

Thanks.

12Ounce · #5 11-28-2007, 03:15 PM

All that stuff is under the "back cover" ... nearly against frame on LH side. 10mm hex screws is all I remember. Maybe something smaller once under the cover.

I would strongly suggest you go to Ford parts counter and get a print-out of the exploded view of that end of tranny. Let the counter guy point out the various solenoids and valves. He should know how and be willing to do this.

BTW, you mentioned the temp sensor ... its also under the end cover. Cheap little gizmo ...easy to replace. If its bonkers ... that may be the only problem!

knl25 · #6 11-28-2007, 09:12 PM

Quote:

Originally Posted by 12Ounce

All that stuff is under the "back cover" ... nearly against frame on LH side. 10mm hex screws is all I remember. Maybe something smaller once under the cover.

I would strongly suggest you go to Ford parts counter and get a print-out of the exploded view of that end of tranny. Let the counter guy point out the various solenoids and valves. He should know how and be willing to do this.

BTW, you mentioned the temp sensor ... its also under the end cover. Cheap little gizmo ...easy to replace. If its bonkers ... that may be the only problem!

I have several questions before proceeding with the replacement:

-It seems like there are 3 different kinds of solenoids: pressure control solenoid, shift control solenoid and lock-up solenoid, according to rockauto.com, so which one is the one I should try first. I want to be prepared before going to Ford parts dept.

-I took a look under the hood and it seems very tight where the "back cover" is. How did you take the cover off after uncrewing the bolts. Did you do this under the car? And do I need to take all the fluid out before taking off the cover?

Thanks for the help.

12Ounce · #7 11-29-2007, 07:07 AM

The cover will come off from under the car. Be sure to clean around the cover edges as good as you can before removing screws. No, do not drain the tranny ... but you will lose a wee bit in this process. The gasket is reusable.

I don't know that much about trannies. I went to the Ford dealer AS my preparation. So I can't answer your questions about component ID. I would make my first effort just to replace the temp sensor ... you could buy that single part ahead. Then maybe the pressure control. You could take a digi photo when cover is off ... and the dealer parts guy should be able to point out what's what.

Some of those parts are pretty pricey!

EDIT CORRECTION: As I look under the hood, I remember things a bit differently. (Too many different car repairs this year!) The screws are 8mm heads. There is plenty of room between the cover and frame, but the tranny mount and support tube must be removed. I think I worked mostly from below ... but also from above. The air filter, battery and battery box look as tho they need to be removed.

tomj76 · #8 11-29-2007, 11:47 AM

It might be worth your while to subscribe to an on-line manual. The AllDIYData manuals are often reccomended, but I've never used them. I've used the Motorcraft online manual, and found it to be as good as the actual shop manual. These are located at: http://www.motorcraftservice.com/vdi...=productdetail

Accurate information has a habit of paying for itself.

I don't know if the TCC selenoid is the same as the Lock-Up selenoid. Ford uses the TCC term. Advance Auto Parts lists the TCC for my model year for $46.99 (TCS65).

Consider taking it to a couple of transmission shops for an estimate. When I did mine, I took it to several shops. Some actually looked at it first while others just assumed it would need a complete overhaul. However, each time I had a chance to talk to someone who taught me something that has helped in the long run.

12Ounce · #9 11-29-2007, 03:50 PM

(I had to edit my previous posting.)

Tomj76:
That's a good link. Thanks! With paper manuals costing around $200 or better, ... its not that bad a deal.

Can you print out the info?

tomj76 · #10 11-29-2007, 04:11 PM

Yes, I printed out the pages I needed and took them into the shop with me. About six months ago I purchased a hardcopy of the '96 Windstar shop manual for ~$100. I believe it came from Helm, Inc. which I found through the Motorcraft website.

wiswind · #11 11-29-2007, 08:12 PM

Helm is THE official source for FORD shop manuals.
My local dealership has a sign that states this at their parts counter.

knl25 · #12 12-27-2007, 07:14 PM

Hi guys,
I finally got some time to replace the TCC solenoid and temperature sensor inside the valve body cover. Here's a pic of the part if someone needs it

I took the car for a 100mi trip. For the first 500mi everything seems fine, but unfortunately the damn code P0741 came back (i had a scantool hooked up for the trip to monitor)

. I also noticed a little hesitation and jerk (maybe between 1st and 2nd gear). It occasionally does this but not always.

Now the question is what could cause the TCC stucked off besides the solenoid? Is there anything else I could try to test before taking it to Ford.

12Ounce · #13 12-28-2007, 01:42 PM

I believe the temp sensor is behind the mount bracket in the photo. Did you change that?

knl25 · #14 12-28-2007, 02:23 PM

Quote:

Originally Posted by 12Ounce

I believe the temp sensor is behind the mount bracket in the photo. Did you change that?

Yes I changed the temp sensor also ($8 part !).

Just stopped by Ford service dept but they wanted me to leave the van there for the whole week because they cannot take a look at it right now. I really need the car and didn't leave it with them.

The car runs fine for the most part in town. My engine is pretty new (around 10Kmi), so I wonder if it's more economical in the long run just to replace the transmission (140Kmi on the current transmission) with a remanufactured one since it would likely cost several hundreds to have this problem diagnosed and fixed, and whatever is about to come next.

The labor is 12 hours to install the transmission which is about $1100 at the dealer. You mentioned in the other post that it cost you about $1500 for the remanf transmission? How much is the shipping for the new one and the core back to them?

I'm just preparing for the worst but really hope that I don't have to go this route.

Thanks!

12Ounce · #15 12-28-2007, 05:40 PM

There was no shipping cost as it was a dealer stock item. IIRC the core charge was $600. I used my little Nissan truck for the shipping to/from the dealer's dock.

If you are using this van just for in-town use ... it may last you a long while just as it is.

If you do replace or fix the tranny ... replacing would get my nod.

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