AdBlue warning light/reset fault W166

[ajlsl600]

this system seems to be one of the latest headaches and cash grabbing schemes . my ml 250 has had the tank.heater.injector changed at 50k miles as well fortunately prior to my ownership ,but it seems a really common occurrence/expense my question ,WHY cant this stuff be reliable and at least cheaper to replace. 600 + for 2 nox sensors that often dont last is nuts. prob £10 to produce.

 

[John Laidlaw]

Hi Guys. I've had this warning problem too. The Adblue tank is full but the warning comes on and says I have 497 miles left until the engine will not start. This then counts down as I drive. I get this reset by the garage but it comes back on again after about 20 miles. As a workaround I was going to buy one of those digital monitors and try to reset it myself. Can anyone recommend one that works well with an E-Class and allows you to delete and reset notifications?

Welcome Mark
hope a member who still has one can check for you but the icarsoft MB2 diagnostic tool MIGHT just do this (I had one but sold when I crossed briefly to the dark side)

 

[jjp35]

Hi Guys. I've had this warning problem too. The Adblue tank is full but the warning comes on and says I have 497 miles left until the engine will not start. This then counts down as I drive. I get this reset by the garage but it comes back on again after about 20 miles. As a workaround I was going to buy one of those digital monitors and try to reset it myself. Can anyone recommend one that works well with an E-Class and allows you to delete and reset notifications?

Hi Mark, Is your EML light is on as well.

I had the same problem with my ML also my EML came on as well (see my post above). I tried icarsoft MB V2.0 but it could not clear fault on my ML. Saying that it might work for your car.

Mine was sorted out by Software Update and reset at the Mercedes Main Dealer cost me £168 + Vat. I was told by an Independent MB specialist in Kent to take the car to Main dealer. According to him it is best to get software update done by the main dealer while there computer is connected online to the Mercedes main server.

My friend recently had same problem on his ML, even after Software update and reset at Mercedes dealer, the EML light came back after few hours. When he took it back to Mercedes, further investigation by Mercedes found Blown Fuse to NOX sensors.

Please check fuses, it might solve the problem without needing software update.

Hope this helps.

PS. If you mention where do you live, some member near you might lend you Icarsoft MB to try.

 

[Mark Cairns]

Hi Mark, Is your EML light is on as well.

I had the same problem with my ML also my EML came on as well (see my post above). I tried icarsoft MB V2.0 but it could not clear fault on my ML. Saying that it might work for your car.

Mine was sorted out by Software Update and reset at the Mercedes Main Dealer cost me £168 + Vat. I was told by an Independent MB specialist in Kent to take the car to Main dealer. According to him it is best to get software update done by the main dealer while there computer is connected online to the Mercedes main server.

My friend recently had same problem on his ML, even after Software update and reset at Mercedes dealer, the EML light came back after few hours. When he took it back to Mercedes, further investigation by Mercedes found Blown Fuse to NOX sensors.

Please check fuses, it might solve the problem without needing software update.

Hope this helps.

PS. If you mention where do you live, some member near you might lend you Icarsoft MB to try.

Thanks so much. I'm taking it in to a non dealer tomorrow, at least they can reset it and give me another 500 miles. I know they did some kind of reset that involved them connecting it to Mercedes in Germany but it didn't solve the problem. I will ask them to look at the fuses as you suggest. If anyone has an Icarus somewhere in London they can lend me that would be great. I'm a driver for a TV production company and work long hours and the car is essential to my income. The simple error message is turning into a nightmare!