amanj

I am having some issues with my 2015 GLK250 transmission.
Roughly 60,000miles (100,000km)

I cannot put it into manual mode and cannot use the paddle shifters.
Pushing the paddle shifters does nothing.
It also does not downshift until the very last possible moment at around 900rpm.
If I give it gas to pass someone on the highway or go uphill, it still does not downshift.
I can push the accelerator all the way down and it still won't downshift.

No error codes, and MB dealership just updated the ECU and transmission control module (as part of field measure device install).
The transmission control module was updated without issues.

Has anyone experienced this before?

Mmr1

When was the last oil change?

amanj

Approx 2000km ago, done in March

andreigbs

Assuming you've had the AEM fix, so the entire powertrain is now covered under this warranty.

Take it to the MB dealer and make them fix it on MB's dime.

amanj

I took the truck to MB initially for the transmission issue. They then advised they will do the AEM work and had an outstanding recall as well.
Will this extended warranty still apply even though they are aware the transmission issue was prior to the warranty being initiated?

Thanks.

andreigbs

Whether they're aware or not is immaterial; the facts are (1) they "updated" the TCM, (2) they performed the AEM which includes ECU software updates.

The AEM warranty alone would cover powertrain-related issues. On top of that, whatever TCM update they did clearly didn't fix the transmission issue.

Codes or no codes, they're on the hook to figure it out now and fix it, and MB corporate will be paying them.

karmikan

This is an extract from the Bluetec Settlement document detailing the items covered by the post-field measure extended warranty. There's a good chance that your issues are related to either the TCU or the HCU. Most service advisors have no clue what is or isn't covered so you will probably need to escalate to the service manager and mention the terms of the Settlement. In my case (PM sensor on wife's car) even the Service Manager was clueless but eventually caved. Just stick to your guns. Good luck.

Covered Parts. The Extended Modification Warranty shall cover the cost of all parts and labour needed to repair the items listed below:
Catalysts o Diesel Oxidation Catalyst o Diesel Particulate Filter Assembly o Selective Catalytic Reduction (SCR) Catalyst Diesel Exhaust Fluid (DEF) System o DEF Injector o DEF Injector Controller o DEF Supply Module o DEF Pump o Temperature Sensor Unit Parts of the Fuel System o Fuel Injectors Parts of the Exhaust Gas Recirculation (EGR) System o EGR Cooler (including bypass control) o EGR Valve o EGR Temperature Sensor o EGR duct Other Sensors That Are Covered o sensor where equipped after Field Measure) o NOx Sensors o Intake Manifold Pressure Sensor o Particulate Matter Sensor o Exhaust Temperature Sensor Engine Control Unit hardware (where replaced as part of Field Measure) Transmission Control Unit hardware (where replaced as part of Field Measure) o Hydraulic Control Unit hardware (where replaced as part of Field Measure) o Air intake throttle Intake manifold/charge air distributor Instrument cluster hardware (where replaced as part of Field Measure) Cylinder Head Assembly components: Valves, Springs, Valve Spring Keepers, Valve Seats, Cam Bearing Caps, Camshaft, and Manifold Studs Engine timing chain Turbocharger, including VGT actuator Coolant thermostat (where replaced as part of Field Measure) Crankcase Ventilation Valve (including line and heating element)

Santafe13

I just encountered the same issue on mine coming off the highway I couldn’t downshift to get more speed and paddle shifts were not working or manual mode. I pulled over turned it off and back on and it was fine after that. Seems like a software issue, I just got a fresh oil change from the MB dealer and they did the water pump Diag recall so not sure if any of this had to do with it but has never happened before.

curious @amanj did you issue get resolved ?

Bill0004

This exact thing happened to me last week. I felt a very slight clunk, the transmission dropped from D7 to D6, I lost about half my throttle and paddles didn't work. I got the car home okay, and the next morning it was fine again. Going to schedule a service before I hit 120k since the AEM covers the transmission as well.

Santafe13

Mine ended up being a punctured air cooler hose (driver side) which is very common and Mass airflow sensor - it was going into limp mode. Engine light came on when the mass airflow went.

hope this helps.