P0744 Torque convertor clutch circuit intermittent

[burner]

Hi all,

I'm trying to troubleshoot my 2013 Spanish built D40 which is throwing the above error a couple of times a week. 2 nights ago, I stripped out the valve body from my transmission and then pulled our and cleaned the solenoid. Transmission was very clean inside and tray/magnets were clean. When I plugged it into a 12v battery I could see the solenoid shut and when I blew into the open end I could feel the wind only coming out the pin hole, so it seems to be working. I put it all back together and drove it for 30 minutes the next day and didn't have any issues. I had the reader plugged in and was watching the live data of the TCC solenoid and could see that the solenoid was reporting anywhere from .3 to .61 Amps when I was in 4th/overdrive. That evening we drove the car for another 30 minutes. I had the reader plugged in and my wife noticed that the read out after about 5 minutes of driving stopped showing the same Amps and instead got stuck at .1 Amps. The next day I drove the car and same deal, couple of minutes with current then down to .1 Amps and then a few minutes later the P0744 error popped up and the engine light came on.

I guess the error is correct, the issue is intermittent and I'm wondering if there is a count on the number of failures before the P0744 error is thrown? Has anyone had this intermittent issue and has replacing the solenoid fixed it, or am I looking at a replacement valve body in this case?

Attached are some pics of my valve body and TCC solenoid (2nd from left). The Solenoid is a Bosch brand P/No. 0260130031. I believe it's a RE5R05A transmission, however the label on it reads JATCO Corp, Model: 3HX8E.

I'm located in the outskirts of Melbourne (Australia), does anyone know a good place for parts?

 

[Old.Tony]

I wouldn't pay a lot of stock in the 3HX8E designation. If yours is a 5-speed from a Navara, it's an RE5 (they ALL have this box) - I have the same gearbox and I've attached a pic of the Jatco tag from mine.

My TCC started slipping and there was a figure the mechanic looked at indicating the slip rate in %, my symptoms were that when the gearbox began to try locking the TCC the gearbox would vibrate because the TCC would attempt to engage, slip and disengage, then try again (rapidly). This was apparently because the material on the face of the clutch had worn quite thin, and it was a common thing. He even described how they mechanically remove the old material and affix new material in its place.

I don't know where I'd source parts. In the end the mechanic destroyed my gearbox by connecting the transmission cooler lines to the radiator and flooding the gearbox with coolant. Another company attempted to repair the damage and I had to dump that gearbox and put a 2nd hand one in.

I hope this is a little useful to you.

 

[burner]

Just posting back here my update.
Before Christmas, I pulled the valve body out of the transmission, and pulled the TCC solenoid out. I gave it a clean and plugged it into a 12v battery and was able to see it open and close. I put it all back together and it seemed fine for the 1st drive. Upon the 2nd drive, I got the same error I monitored the Amps on the TCC Solenoid using Live Data on my OBD2 reader and when this happened, the solenoid reported 0.01Amps.

I then ordered a replacement from Amazon and received it last week. So far after almost a full tank of diesel there have been no more errors reported, so I'm calling it.....fixed. I can see now with the OBD2 reader when I let the gas pedal go above around 80kms, the TCC solenoid reports 0.00 Amps, then as I touch it, it starts rising.

I ended up re-using the same oil because it was only around 15,000kms old. No signed of any filings on the magnets or sump. I had to top it up each time due to some spillage.

For anyone else, it's a real PITA to re-fill this transmission. I used the Allen key plug at the front of the sump with a SuperCheap Auto 1 Litre pump action plastic filler bottle then used half a small Bunnings garden dripper riser (the ones you screw into the 13mm black pipe and then screw the small sprinkler head into) shoved into the filler bottle hose. I had to grind it down a little to fit tightly into the hole in the sump. After about 4 litres, I started the engine to put the oil back into the Torque converter, then continued filling after turning the engine off. After about 5 litres the oil started coming back out, so as I pulled the Bunnings pipe out, I put the screw in each time until all 8 litres that came out was back in again.

 

[Old.Tony]

Great stuff - I wish I'd known this before, but that's the way things go.

Do you know the Mode + PID combinations to get the data from the auto trans? I don't have a workshop OBD tool, just a bluetooth module and the Torque app, and it doesn't include any custom Nissan PIDs.

 

[burner]

My Foxwell device doesn't tell me the codes.
All I can get is TCC Solenoid: 000A, not sure if that's helpful