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2005 E320 CDI – P0705 Code, No Shift, Stuck Shifter – Need Help
Hello MBWorld,
I’m hoping someone can help me troubleshoot an issue on my 2005 E320 CDI (W211) approx. 220K miles. I don’t have access to a workshop as my new shop/garage is under construction. I have most of my tools in a storage unit where I can’t work on cars, so I am limited. If I can figure out the problem I could perhaps fix in my driveway. For a scanner I usually use a Creader Elite 2.0T scanner (used mostly on our Lexus vehicles, customizing settings/programing keys etc.). I haven’t purchased the MBZ upgrade for it yet, since I’m unsure whether it would offer deeper insight into the P0705 code I’m seeing.
Symptoms:
Car won’t shift out of 1st gear (limp mode?)
P and S lights on dash are generally off, will go on if the car idles for a long time. This intermittently will allow the transmission to shift normally.
Reverse lights don’t appear work in R
When stopped, the shifter won’t move past Neutral into Reverse or Park
If I release the brake pedal, it lets me shift into R or P
This has been an intermittent issue for a while, the vehicle is a 4th car and I wanted to swap the om648 and 722 into a w460 G when the shop is done.
The p0705 code often clears but then the car stays in limp mode because it’s a pending code?
I’ve spent some time researching and found a few common causes:
Shifter module failure, although I don’t think anything has spilled in there?
Transmission connector plug leak causing fluid to travel into the TCU. I saw a youtube that pulled the passenger ( USA) floor mat and cover and did not see any sign of trans fluid. Is this where ethe TCU is located? Would Trans fluid be obvious, I might not have dug deep enough?
Conductor plate inside the transmission may be failing (bad range sensor / solenoids)
The scanner pulls:
P0705 – Transmission Range Sensor A Circuit (PRNDL Input)
Has anyone dealt with this on a CDI? Does the P0705 lean more toward the shifter, connector plug leak, or conductor plate?
Also, is it worth investing in the MBZ software upgrade for the Creader Elite 2.0T,
Any advice is appreciated. My wife is ready to donate the car if I can’t sort this out soon, so I’d really like to try to fix it myself if possible so if we donate or I keep for the G swap.
if there is no direction on this, where does the ATF enter the harness and TCU ( passenger footwell or under car)? I can look to search that further. RE the gear selector, are there signs like a cold solder joint?
@Belson
Rough rule of thumb, electrical faults in the 722.6xx transmission must be cleared with a MB-compatible scanner. Hydraulic/mechanical faults will clear with key off/on/off.
.pdf attachment shows location of modules on the W211. To access the TCM pull back the carpet on the passenger side where the passenger's feet rest. The modules are under the passenger's feet against the firewall, NOT the floor board! Pull back carpet, remove three each 10mm plastic nuts (one at top, two at bottom and one of those is a PITA to get to!). Tilt metal plate towards seat and the modules are all attached to the other side. You can then inspect TCM for fluid intrusion.
In my opinion (just opinion and where I would start), I would look at possibilities from most to least likely.
-Electronic Shifter Module on the transmission tunnel. If so, see this: https://mbworld.org/forums/w211-amg/...5-19-32-a.html
-Possible failing TCM.
-CANBUS issue involving the ESM and TCM.
The codes below point towards the Electronic Shift Module but I would confirm with a STAR/Xentry diagnostic tool or equivalent. If so, the detailed code should show up as a P1856, "Selection position lever detection has failed". Note that there are four each sub-codes that fall under the P0705. The DTC 18 matches the symptoms on your car. If it is the lever selector module, replacement will take you 3-5 hours and a rebuilt sensor module is available for under $150. It will not need to be coded to the car.
Last edited by bbirdwell; Jun 5, 2025 at 02:48 PM.
Hi,
After having worng gears selected/no gears showing on dashboard readout/ and locking in gear I changed the Gearshift module and all works as it should. It appears the TCU diodes (Circuit board within the centre console module beneath the gearshifter) gets dirty and looses solder contacts.
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