Code P374a - transmission
#1
MBWorld Fanatic!
Thread Starter
Join Date: Jun 2008
Location: Los Angeles
Posts: 8,061
Received 2,842 Likes
on
1,677 Posts
2012 P31 C63 Coupe Trackrat, 2019 GLE63S Coupe Beast
Code P374a - transmission
My Autoenginuity scanner is showing this code, but it is "Unknown Trouble Code Description".
Car was shifting really hard yesterday on track in "S+". Going back to the hotel in "C" mode, felt like the trans was slipping 1-2 and 2-3. Today feels clunky/hard going into 3rd. Manual mode feels better, but downshifts are rough.
Has anyone had this code? I can't find any information on it. Would be really disappointing if I find out the trans can't take even one HPDE. Thanks
Car was shifting really hard yesterday on track in "S+". Going back to the hotel in "C" mode, felt like the trans was slipping 1-2 and 2-3. Today feels clunky/hard going into 3rd. Manual mode feels better, but downshifts are rough.
Has anyone had this code? I can't find any information on it. Would be really disappointing if I find out the trans can't take even one HPDE. Thanks
#2
MBWorld Fanatic!
I have heard of trans slipping on pre-FL cars that had a supercharger (stage 2) with a certain amount of miles on it. I don't recall that fault code and problem on facelift.
What you are describing doesn't sound good though. I hope you'll be able to get it fixed.
What you are describing doesn't sound good though. I hope you'll be able to get it fixed.
#3
MBWorld Fanatic!
Thread Starter
Join Date: Jun 2008
Location: Los Angeles
Posts: 8,061
Received 2,842 Likes
on
1,677 Posts
2012 P31 C63 Coupe Trackrat, 2019 GLE63S Coupe Beast
Thanks. Only 20k miles on my 12. Car still throwing code, but I've been driving the **** out of it all day in M which seems to be just fine. The problem is when it's in an auto mode - inappropriate shift points and hard shifting. Will bring to a dealer soon I guess... ugh.
#5
MBWorld Fanatic!
#6
even with a slipping trans and it popping out of gear my computer never threw a code pre facelift 7g tranny
#7
MBWorld Fanatic!
Thread Starter
Join Date: Jun 2008
Location: Los Angeles
Posts: 8,061
Received 2,842 Likes
on
1,677 Posts
2012 P31 C63 Coupe Trackrat, 2019 GLE63S Coupe Beast
Yes, did the TCU reset. Also disconnected the battery for a couple of hours. Still have the code. In M mode, car feels great. In C mode, the car wants to shift up into 7th as soon as possible, usually by the time I'm at 35mph. Same seems to go for S. Didn't try S+ as that's where I was having the most trouble with the hard shifts and excessive downshifts.
Trending Topics
#8
if it's tuned maybe re-apply the tune, my car was shifting really sluggish and had like no pick up in lower RPMs unless you smashed the gas ..once i re-flashed it went back to normal
#11
MBWorld Fanatic!
Thread Starter
Join Date: Jun 2008
Location: Los Angeles
Posts: 8,061
Received 2,842 Likes
on
1,677 Posts
2012 P31 C63 Coupe Trackrat, 2019 GLE63S Coupe Beast
Never figured it out. I don’t think I’ve used any of the auto modes since. Code is gone.
#12
Super Member
Only found 2 things that possibly pertain to this code. Problem with the paddle shifter and someone who changed their tires and the code mysteriously went away. Not many details
But do you remember what size tires you were running at the time?
But do you remember what size tires you were running at the time?