Hello all,

So I had just receIved my RAS a day before my trip from NJ to St. Augustine/Ft. Lauderdale. Got it installed...Thanks to ALL here on FTE. LOVE YOU ALL! (Damn JC Whitney...Sent me the old style that mounts under the leaf spring hold down plate, so it took all afternoon!) Hopped in the truck for a test spin, and then CEL came on, and the OD off light started flashing. Just my luck. (Murphy is always following me around!) Used my SCT ExCal2 to read the codes and got a P0740 (TOR CVT CLT CIR), P0743 (TOR CVT CLT SYS ELEC FL). Had ZERO time to deal with fixing the problem before leaving for the trip. Trans doesn't sound funky, and shifts into OD just fine. So off I went, with fingers crossed. Fortunatly, everything went A-OK. WHEW! A little hard shift from first to second, but other than that, everything seems "normal" but I'm still concerned. I have a week before I have to do the 900 mile trek back north, but the local Ford dealership here in St. Augustine (Bozard Ford) is COMPLETELY unwilling to steer my in the right direction to fix the problem myself. They act as if the codes are some kind of trade secret and politely told me to go jump in a lake. So I'm here to ask the FTE community for a bit of guidance in diagnosing and fixing this problem. I don't have the funds for a new Trans, so any advice on what to do would be greatly appreciated. Thanks to you all in advance.

 

I'd try a different dealer. I don't know anything about these trans codes though.

I found the following from Google though:

P0740 FORD - Torque Converter Clutch Solenoid Circuit

Possible causes:
- Low transmission fluid level
- Dirty transmission fluid
- Faulty torque converter clutch solenoid valve
- Torque converter clutch solenoid valve harness or connectors
- Torque converter clutch solenoid valve circuit is open or shorted

The torque converter clutch solenoid valve is activated, with the gear in D4, by the Transmission Control Module (TCM) in response to signals sent from the vehicle speed and the Engine Control Module (ECM). Lock-up piston operation will then be controlled. When the torque converter clutch solenoid valve is activated, the torque converter lockup clutch will engage creating a 1 to 1 RPM ratio between the transmission input shaft and the rotational speed of the torque converter.

Lock-up operation, however, is prohibited when A/T fluid temperature is too low.

When the accelerator pedal is depressed (less than 2/8) in lock-up condition, the engine speed should not change abruptly. If there is a big jump in engine speed, there is no lock-up.


P0743 FORD - Torque Converter Clutch Circuit

Possible causes:
- Faulty torque converter clutch solenoid valve
- Torque converter clutch solenoid valve harness or connectors
- Torque converter clutch solenoid valve circuit is open or shorted
- Low transmission fluid level
- Dirty transmission fluid


The Torque Converter Clutch (TCC) solenoid valve is activated, with the gear in D4, by the Transmission Control Module (TCM) in response to signals sent from the vehicle speed and the Engine Control Module (ECM). Lock-up piston operation will then be controlled. When the torque converter clutch solenoid valve is activated, the torque converter lockup clutch will engage creating a 1 to 1 RPM ratio between the transmission input shaft and the rotational speed of the torque converter.

Lock-up operation, however, is prohibited when A/T fluid temperature is too low.

When the accelerator pedal is depressed (less than 2/8) in lock-up condition, the engine speed should not change abruptly. If there is a big jump in engine speed, there is no lock-up.

 

Thanks Sunline,

I know my trans fluid is clean, and there is enough in the box, from what i can tell from the dipstick. need to crawl under and check connectors. Got one off, and it looked good.

I'm thinking that it may be the "Faulty torque converter clutch solenoid valve", so that may be what I change first.


I also took the steering column apart to check the OD wire was not rubbed raw. Was a little worn, so I put some e-tape around the area, but no bare wire to short.

Read on the diesel forum that some people had a this issue and replacing the Alt fixed the problem. Going to try disconnect the Alt, clear the codes and see what happens. Evidently the Alt was creating electrical noise that the ECM interpreted as this problem.

 

Yep, disconnect the battery for a few mins and then reconnect. That often helps to clear the memory of things to see if the problem comes back.

 

so I disconnected the Alt, cleared the codes and CEL went off. Did a little driving around and didn't come back on, OD off light still flashing, but trans feels good. Shifting OK, no change in RPM's, actually felt better with Alt disconnected from first to second. Dropped the hammer and everything felt strong. Rained all day today and I have no covered place to work while here in FL, so I just disconnected the battery, turned on headlights, letting it reset overnight. See what happens in the AM, weather permitting.