AdBlue issue Mercedes SLC diesel no start

I understand your frustration with the AdBlue issue in your SLC Although mine isn't a 2018 model I have experienced a similar problem with the diesel exhaust fluid system It sounds like you are on the right track with the potential cause being a problem with the AdBlue delivery system Specifically, the Selective Catalytic Reduction (SCR) catalyst relies on the proper injection of AdBlue to reduce NOx emissions Did you notice any other symptoms besides the dashboard alert and the car not starting Was there any unusual smell or any leaks underneath the vehicle related to the AdBlue system

Thanks for the quick reply Regarding additional symptoms no unusual smells or visible leaks underneath the car Just the error message and the eventual no start situation You mention the SCR catalyst is there a way to test if the AdBlue is actually being injected properly Seems to me that emissions control is where the problem lies since the engine is blocked now

You're welcome I am glad I can help Unfortunately without specialized equipment and diagnostic tools it is difficult to definitively test the AdBlue injection yourself Given the no start condition and your suspicion of a faulty AdBlue output to the dosing unit it would be prudent to have a workshop inspect the AdBlue tank and the associated lines for any blockages or failures I would recommend that you seek professional assistance to diagnose and rectify the problem

Just wanted to give you a heads up I took the car to the workshop as you suggested They confirmed the AdBlue pump was defective Preventing the fluid from reaching the SCR catalyst It cost me 250€ as estimated to replace but at least the car is running again Thanks again for the help really appreciate it