772.9 Problem

[RKW221]

Hi everyone

I own a 2013 S550 4M and love to work on cars. So I bought a project 2007 S550 with a tranny problem.
Swapped filter and oil and replaced solenoid Y3/8y1. This error was showing before but kept showing after the swap as well.

The idle still seems a little bit rough but stable. I overheated the oil to about 130 before disconnecting the fill adapter and it drained not a whole lot. 114 should be the 45 Celsius... So my mistake there.
After driving coming off the ramps took it slow but about 800 feet later the car stopped and wouldn't shift at all. I turned off the engine and restarted. Car shifted. Driving around the block but car stuttered at 1500 and wouldn't shift to 2nd. Driving a bit more, shifting manually and car started shifting to 2nd but stuttered at 2500 and wouldn't shift to 3rd. Drive around, same symptoms but over 3000 rpm acceleration good, but no upshift

Got back, pulled error codes 2810 and 0894 on the TCM. ECM of course shows 1757 1761 1765 1793.
Weirdly also, for the first time at this diag session (probably the 30th I made): 0983 and 0522.
Car was sitting in the Florida sun for 1.5 years with probably very little movement.
TCU was replaced sometimes in 2010. Now VGS3-NAG2. A003 446 03 10. Large number 3 engraved. Solenoids looked in good condition. Cleaned with magnet and flushed with ATF134 by Shell.

Any ideas?

Weird thing also, the trunk battery posts were very hot, like the whole battery, cleaned posts, tested battery, in good ahape. Just noting because voltage problems can cause TCU issues.
Thankful for any help/ideas before swapping TCU or Valve body.
Richard

 

[brandwooddixon]

Weird thing also, the trunk battery posts were very hot

That doesn't sound right, unless the car has been sat in the sun and the ambient temperature is very high.
Before anything else, have you check the battery voltage both with and without the engine running, just to rule out an alternator overvoltage issue?

 

[Wighty]

Hi everyone

I own a 2013 S550 4M and love to work on cars. So I bought a project 2007 S550 with a tranny problem.
Swapped filter and oil and replaced solenoid Y3/8y1. This error was showing before but kept showing after the swap as well.

The idle still seems a little bit rough but stable. I overheated the oil to about 130 before disconnecting the fill adapter and it drained not a whole lot. 114 should be the 45 Celsius... So my mistake there.
After driving coming off the ramps took it slow but about 800 feet later the car stopped and wouldn't shift at all. I turned off the engine and restarted. Car shifted. Driving around the block but car stuttered at 1500 and wouldn't shift to 2nd. Driving a bit more, shifting manually and car started shifting to 2nd but stuttered at 2500 and wouldn't shift to 3rd. Drive around, same symptoms but over 3000 rpm acceleration good, but no upshift

Got back, pulled error codes 2810 and 0894 on the TCM. ECM of course shows 1757 1761 1765 1793.
Weirdly also, for the first time at this diag session (probably the 30th I made): 0983 and 0522.
Car was sitting in the Florida sun for 1.5 years with probably very little movement.
TCU was replaced sometimes in 2010. Now VGS3-NAG2. A003 446 03 10. Large number 3 engraved. Solenoids looked in good condition. Cleaned with magnet and flushed with ATF134 by Shell.

Any ideas?

Weird thing also, the trunk battery posts were very hot, like the whole battery, cleaned posts, tested battery, in good ahape. Just noting because voltage problems can cause TCU issues.
Thankful for any help/ideas before swapping TCU or Valve body.
Richard

Are you saying (I couldn’t see it) that you now have correctly set the gearbox ATF level ?
Could a lot of the rough running and limp mode be down to bad fuel having gone off and gunged up everywhere after 1.5 years of no use ?

 

[RKW221]

Hi, thank you for the replies. I will check the voltage with engine running on and off to see the charging current going to the batteries. Thanks for that tip.

The fuel - I think it's possible, but the idle is pretty smooth, maybe 10% rougher than my 2013. I put premium fuel in the tank and the car has been run a little bit. I'll put some gumout multi system tuneup in the tank to see if that helps, but the faults in the TCM point me to the transmission. Of course all filters have been changed, they were a total mess... So the engine seems to be getting enough air and fuel at 3000 rpm+ and accelerates nicely, but it won't get out of 2nd. Downshifts also very jerky uneven or non existent.

Yes, it's possible that due to the higher temp of the oil when draining after shifting through the gears and letting it warm up could have lead to a little bit lower level of fluid in the tranny. But the fact that the Y3/8y1 Working Pressure Control Solenoid Valve is still showing "Internal electrical check of component failed", even though it has been swapped for a brand new Bosch still has to bee an issue that interferes with the tranny running correctly. Would you agree?

The Valve body, magnets and fluid looked all very good actually, so I think a contamination should not be the issue, more of an electrical problem. What could cause the fault on the solenoid. I didn't check the new one with 12 volts, it was OEM packaged, but i will put 12 V on the old one and see if it clicks.

The previous owner must have been a total id....t. He painted the chrome, the headrests and plastics inside in ORANGE paint. took me 4 days to clean it all up. So I assume he was not very knowleadgable about cars... He had the car for a couple of thousand miles after the first owner had an amazing service record up to 145000 miles. Car has 151000 now.

Thank you guys for any input
Richard

 

[Bay Leaf]

Worth checking ( probably not related ) the MAP sensor (manifold absolute pressure) I had a Jag that went into limp mode and the gear changes went strange. Fitted a new sensor and all was well. However I did get a code directing me to the said sensor which I don't think you have in your case, but it's worth a try. Good luck.

 

[RKW221]

I actually thought of that today but that would show in the ecu... Behaves similar though

 

[Bay Leaf]

Check the sensor and give it a clean. I won't do any harm even if it doesn't do any good

 

[RKW221]

Yeah you're right. Ill give it a try.

 

[Wighty]

Yeah you're right. Ill give it a try.

Have you changed the transmission electrical plug on the side of the gearbox as part of the service ?

 

[RKW221]

No i have not, is that a part that can cause problems?

 

[RKW221]

Sorry, of course it can, I understand that, but is it prone to going bad? I was super careful pressing it out of the tranny when taking it out.