1998 E320 with weird electrical problems… - PeachParts Mercedes-Benz Forum

pimprig · #1 08-16-2008, 11:00 PM

Hi all, I have a 1998 E320 with weird electrical problems… I noticed the sun roof problem first. One day it seemed like the motor was going out when I tried to open it. It would go and cut as if you were trying to open it by touching two bare wires together. Then later I noticed that I had to point the key fob to the door handle to lock and unlock the car. Then the dome lights in the front won’t turn on at all and the garage door opener doesn’t work either. I have checked all the fuses and they are all fine; any relays to check?

Thanks!

stevebfl · #2 08-16-2008, 11:26 PM

Fuse 4 in the F4 panel under the rear seat powers the roof module.

Matt L · #3 08-16-2008, 11:35 PM

When you're checking that fuse, ensure that there is no water under the rear seat.

pimprig · #4 08-17-2008, 12:09 AM

Thanks! I have checked all the fuses... I'm thinking it could be a relay or a computer that controls the sunroof, dome lights, garage door opener and the receiver for the lock unlock function on the key fob.

stevebfl · #5 08-17-2008, 12:20 AM

The relay or module IS the roof module. The sunroof switch is PART of it.
N70

pimprig · #6 08-17-2008, 12:26 PM

Thanks Steve, does that relay also provide power to the other things that are not working? Or is it just for the sunroof?

stevebfl · #7 08-17-2008, 12:40 PM

MB along with most other manufacturers use a network of zone controllers. Small computers that talk on the network. They interpret and communicate sensor data from sensors close by to other controllers farther away and the drive elements that are also in their zone. An example here would be that the roof module has the inside air temp sensor. It interpretes the temp and sends it over the network to the A/C controller (it does this digitally rather than actually separate wires). Another sensor up there is the radio sensor for the remote control (I think radio rather than infra red).

It of course has the sunroof controls and also has the rain sensor for the intermittant wiper I think.

Unfortunately, after checking the fuse the next step is to communicate with the module and see if it is upset about something.

pimprig · #8 08-17-2008, 12:46 PM

got it! thanks Steve... do you know if there any way I can check the N70 or do I just have to purchase one?

stevebfl · #9 08-17-2008, 12:48 PM

Can you talk to it?

pimprig · #10 08-17-2008, 01:04 PM

Sure I can try! I talk to my car all the time. What should I ask it?

stevebfl · #11 08-17-2008, 01:20 PM

Ask it how it is doing.

But of course the most important issue is whether it answers. And it has to be N70 that answers.

92300SE · #12 08-17-2008, 01:32 PM

MB had several updated parts for the sunroof controller /switch,all poor quality,it is one hard to find part, used,because the new ones are outrageous,I belive 500$,common part to brake and sunroof will be stuck,I belive all models up to 2001 are affected,dealer allways keeps a good stock on those parts,unless you have a unusual interior color to match...

pimprig · #13 08-17-2008, 03:42 PM

Alright Steve, I went looking for the famous N70 but it was no where to be found in there. I think it ran away! That explains the problem…

I took a few pictures for you to see. I also replaced the fuse #4 in the fuse box underneath the back seat. Also everything on fuse box photo A and B that shows #4 does not function. What component does that fuse power?

pimprig · #14 08-17-2008, 03:48 PM

I hope thats not my problem 92...
Personally I think it’s a relay or a component that controls multiple things. Or like Steve said the car does have a can bus system so a component may be shutting others down, down the line.

stevebfl · #15 08-17-2008, 04:56 PM

Upper left 208 820 19 01 repl by 208 820 40 01.