I'll try to make it thorough and simplified.

Issue: Transmission seemed in neutral while in "D" at a roll.
1. Mileage= 187k
2. No transmission issues since purchase in June 2015
3. Changed the trans fluid and replaced with Honda oil in June 2105.
4. "D" light flashing on instrument cluster.

Diagnostic scanner used - Verus Edge 15.4 from Snap On Tools.

1. Scanned the vehicle selecting the VIN# specific and the global side of the cars computer.
2. Codes found: P0740- Torque converter clutch circuit stuck open.
P1656- Transaxle system malfunction.
3. Printed out a diagram of where any solenoids were that could cause the stuck open code.
4. Using the scanners troubleshooter I checked each solenoid component for proper ohm value. All checked good. No needless replacing good parts!
5. Checked each solenoid with 12v and made sure each solenoid functioned when tested. All checked ok.
6. The last step in the troubleshooter stated if all checks fine, suspect internal transmission failure.
7. Sometimes a solenoid could be bad and still work but, not the norm.

Towed the car to my reputable transmission shop and informed them I diagnosed it with the same scanner they had but, feel free to check it yourself. They did. Same results.

After the transmission was removed and disassembled they found 3rd gear clutches were burnt and 2 of the 3 bearings in the case were sloppy but, all bearings were still useable.
The case was sent off to be re-sleeved and the bearings put back in place.
The torque converter will be replaced as well.
3 transmission mounts were found worn or cracked and will be replaced.
The internal filter screen was sucked through the intake hole stopping up the fluid flow ultimately burning up the clutches and the starving the torque converter.

Here are the pictures of the car and the transmission components after removal. Parts uncleaned.

Words of wit:
Always use a reputable scanner (not the autozone freebie) and component check prior to wasting time and money parts swapping. Use your lab scope as well where needed. Diagnosing correctly saves time and money.
My personal shop owner friend only charged me $1000.00 to do the whole job and guarantees it's bullet proof from here on out if not abused. Pretty simple, it wont be abused like the previous owner. He also stated I shouldn't change the transmission oil like I did either. Not broke don't fix it! Trust only a reputable shop as well.

I hope this post helps out others with their 2006 TL having similar or the same issues.

The car


Internal components in roll tray.


Burnt 3rd gear clutches


Drum where burnt gear clutches were


Case with the 2 loose bearing housings


Bad transmission mounts (worn, separated or cracked)
2 on cradle 1 on frame in engine compartment

 

Concise, yet thorough problem, resolution, and visual presentation. This will help.

Thanks.

 

You betcha!

 

Bad news. After all this was done the 3rd gear acted up again. They went back through it and replaced everything and the tech said it operates ok but, still doesn't like the way it's performing. So, out it comes again for a more in-depth look at what is causing the issue. Nothing is being charged as it's under a warranty from the shop. I know the owner is getting fed up with it and is thinking putting an re-man in it or giving me the money back for the 1st repair and be done with it. I hate that last part because it leaves me out and am a friend of the owner. Knowing foreign cars transmissions are different than domestic is their some certain tolerances or specs that he's missing that make it 3rd gear everytime? It was completely gutted and redone so could it be bullschit parts? Funny how it's 3rd gear constantly. Any ideas?