transmission limp mode

[zorpio]

Hey guys i have a 2001 c270 cdi 80,000miles.. I got the car a few weeks ago and and i put my foot down it jumped out of gear then put it in neutral and back into drive and it was fine, then the next day it got stuck in second gear i had to turn ignition off and on and its fine until i floor it again.. then a few days later it got permanently stuck in second gear and wound not reset even if i turn off and on the ignition.. so i took it to a garage and they put there diagnostics on it and reset it and i got the codes and it was changing gears but would still jump out of gear and get stuck but i could still turn ignition on and off.. then again it got stuck it second gear permanently so again to the garage got it reset but this time they wound not give me the codes.. also it feels like the car doesnt want to change like jerks a few times before changing and sometimes it drives perfectly like its brand new.. it still has the Mercedes seal for life on the transmisson fluid so does that mean its never been changed?? iv seen on the forms people are saying it could need new transmisson fluid or needs a new electroplate?? here are the codes the first time i took it to the garage
014 RPM Comparison N2 To N3 Implausible
110 RPM Comparison N2 To N3 Implausible
136 CAN Communication Disturbed Electronic Ignition System Module Or IC
146 Inadmissible Transmission Ratio

does anyone know what these codes means??
thanks alot for any help, means alot its my first merc

 

[Tinytots]

Hi mate,

I have a 2001 E320 CDI auto and mine did exactly the same thing last week

I changed the oil and filter, but also change the plug in the gearbox. The plug cost £26 from Mercedes and was a pinch to fit

Although this was changed it will stay in limp mode until you get the car put on STAR and get codes reset.

I was going to change the conductor plate, but decided to wait to see if the above worked because the conductor plate is £210 + vat in Mercedes or £138 new on eBay.

The oil, filter and plug (7mm bolt) is very easy to do, but the conductor plate is more difficult and you need operating theatre clean conditions to do it.

There's a 6 part video on You Tube showing how to do it, which is excellent.

Hope this helps

 

[zorpio]

Hey thanks for the reply, so just wondering did changing the transmission oil and filter and the gearbox plug fix the problem? hope it has

 

[MBSpecialist]

it means that the scan tool cannot say exactly what is happening to the engine because the ecm parimeters are off at a point in the engine drivetrain system.
Those codes to me indicate the scan tools "best guess"

the dealer or local garage may want to change your conductor plate,...

Message me if you want

 

[panason1c]

Just fixed mine which was going into tranny limp mode, it was the conductor plate 'speed sensors' causing the problem, quite an easy job to replace the c/p......took me about 3 hours (car on ramps...on my back!!) including faffing about, refilling system, road test, clearing up after, etc..Got my c/p off ebay, £135.....it had the original mb logo and part number stamped into it.

As you still have the seal on the dipstick I would check the oil level using the special mb dipstick.....assuming the level is ok, read on.

First thing to check is the gearbox electric plug for leaks, remove the plug from the side of the tranny (release the locking lever and pull out the plug), if any oil dribbles out that means you need a new pilot bush which is very easy to replace....if it was leaking, you then also need to check that the transmission control unit (tcu) which is located inside the cabin, isnt contaminated with oil due to the oil travelling from the gearbox along the inside of the loom and into the tcu, you will need to open up the plastic casing of the tcu to look inside for signs of oil. If there is oil inside just use an electrical cleaner spray and give it a good dosing to remove the oil residue.
Have the codes cleared and road test the car.

If the problem is still there, Changing the oil and filter will be a waste of time and money, that alone won't help.

I would suggest you then renew the conductor plate (which all seem to fail sooner or later anyway) and obviously, oil and filter, also, whilst the valve body is removed, and, bearing in mind your false neutrals and jerky changes, renew some of the valve and spring components....see the attached video link...hope this helps.

https://www.youtube.com/watch?v=vpQlnibuZdo

ps........ if, after all the above you still have a problem, try 'borrowing' another tcu to plug in and try. (as long as another tcu has identical part numbers it should be plug and play)

Note that after any repair, the codes MUST be cleared, otherwise, the remaining fault codes in the tcu will still force limp mode even if the fault is repaired.

 

[imelrose]

I've just fixed mine as well. I've got a 2006 C320 CDI. I'm not sure it's the same issue even though the symptoms were similar. My gearbox refused to kick down and it turned out to to be a fault manifold servo motor that restricted the power massively. In the end I had the gearbox oil changed, which made a surprising difference, and a new servo motor fitted.

 

[Seanposs]

I've just fixed mine as well. I've got a 2006 C320 CDI. I'm not sure it's the same issue even though the symptoms were similar. My gearbox refused to kick down and it turned out to to be a fault manifold servo motor that restricted the power massively. In the end I had the gearbox oil changed, which made a surprising difference, and a new servo motor fitted.

Hi there I have same car as you an mine is doing the kangaroo style driving then into limp mode. If I stop turn car of then it's ok. I noticed to when put heater on eithe cold or warm like a electric fire smell when first turn fire on. If you get what I mean. The car doesn't always do the kangaroo an limp mode just sometimes. Is it the MAF sensor ?

 

[zorpio]

thanks for the reply's .. Ino im abit late on a update but its worrking now, just had the gearbox oil and filter change and its changing gear fine now