Hello,

I have a 2005 E500 RWD. I bought this 2 years ago and when I first bought it, the SRS light would come on and off randomly. After a couple months, it stayed on and wouldn't turn off. I took it to a friend who has a Autel high-end scanner/programmer and I found a code which basically told me I needed to recalibrate the WSS (weight sensing system). So I followed the procedure to recalibrate it but I couldn't get the seat to the "zero point" and it suggested I replace the entire seat or just the seat frame. It also had a code regarding the module N2/7 I believe.

I couldn't find any information about the module n2/7. I believed it to be the airbag module behind the center console , so I took it out and took it apart and took a look at it, I didn't see any damage to it regarding the actual board or components. I used a toner to find the wires that go from under the seat where the 4 sensors plug in, and they did lead to the airbag module connector.

There is a screen on the scanner that shows real time data about sensors etc. And it showed 0 pounds on all 4 sensors even while sitting on the seat. It also said something like "knock on the back of seat to release *something* that's tight and won't let the system set the zero point"

I can get exact codes and pictures in a couple of days. Does anyone know how to set the zero point or what that thing is that is tight and needs to be knocked loose?

I don't believe that all 4 sensors failed, is there any way to troubleshoot which sensor it is or test the airbag/n2/7 module?

Is module n2/7 the airbag module in the center console under the cd changer? Should I change just the seat frame or both the seat frame and the airbag/n2/7 module?

Any help is very much appreciated,

Thank you.

PS I tried programming the SRS module out of the system but it still kept the SRS light on there. And I cant use the srs seat emulator because I already tried to recalibrate it so I need to finish the recalibration before it'll read any sort of signals from that emulator

 

Some info to better understand system, see attachments.

 

Thank you!
I see there is a system n2/13 labeled as the WSS module. Any clue on where that's located?

As well I don't see any sensor that sets the "zero point" only the 4 sensors on the seat frame for the actual weight sensing. Does anyone know on how it sets that zero point?

 

CU (n2/13) is located under passenger seat - compatible part #s (150 in diagram), sensors (140).