Experiencing issues with your lumbar support in your W221 Mercedes-benz? It’s a common concern, and often the solution lies in verifying the system’s coding. This guide will walk you through checking and adjusting the lumbar support settings using diagnostic tools, ensuring your system is correctly configured for optimal comfort.
If you’ve encountered a situation where the lumbar support actuation test is missing from your diagnostic menus, or you suspect incorrect coding after a software update, this step-by-step process is for you. We’ll focus on accessing the relevant menus within your diagnostic system to confirm and, if necessary, correct the lumbar support coding.
First, ensure your diagnostic tool is properly connected to your W221 Mercedes-Benz and you have entered the vehicle identification number (VIN). Once connected, navigate to the control unit selection menu. Instead of running a quick test immediately, manually select “Control units”.
From the control unit menu, proceed to the “Seats and doors” section. Here, you’ll need to choose either “ESA-FR” (Electric Seat Adjustment – Front Right) or “ESA-FL” (Electric Seat Adjustment – Front Left), depending on which seat you are addressing. Select the appropriate seat module to continue.
Within the chosen seat menu, look for “Control unit adaptations” and select this option. Next, choose “Read coding and change if necessary”. This will lead you to the version coding settings for the seat control unit.
You should find a list of coding options. Scroll down until you locate “Lumbar support adjustment”. It’s crucial to check the current setting. If it reads “NOT PRESENT”, this is likely the reason for the lack of lumbar support function and diagnostic menu options. Change the setting to “PRESENT”.
Additionally, verify another related setting: “Pneumatic pump for lumbar support adjustment”. This setting should be configured to “Lumbar support adjustment with series pump”. Ensuring both of these settings are correctly configured is vital for the lumbar support system to operate as intended in your W221 Mercedes-Benz.
After making these coding adjustments, return to the main menu and navigate to the “Actuations” menu. You should now find the “Lumbar support adjustment” selection available. Enter this menu to perform an actuation test and confirm if the adjustments are now functioning correctly.
It’s worth noting that if the lumbar support was incorrectly coded as “NOT PRESENT”, it could explain the absence of fault codes even when the control unit is disconnected. While it’s unusual for these settings to change spontaneously, software updates or previous diagnostic procedures could potentially alter the coding. Therefore, verifying and correcting the coding is a fundamental step in troubleshooting W221 Mercedes-Benz lumbar support issues. By following these steps, you can systematically check and rectify the coding, potentially resolving your lumbar support problem and restoring the comfort you expect from your Mercedes-Benz.
