Help on K40 relay on 2003 E320
 

Starting today the ESP,BAS,ABS came on and tonight I've been reading the posts about the problem, and some say replace the K40 relay. The ABS icon is on in yellow in the tach screen. also.

There is a relay on the K40 module. Should I change the relay since that would be the cheapest thing to do I would think, or is everyone replacing the K40 module including the relay?
Last week we started having an issue of the dash lights blinking as the AC fan cuts out and the radio cuts out. This happens for just two seconds only, and the engine never died.

The dealer replaced the break light switch two years ago when they replaced the brake fluid reservoir so I'm trying to rule that out for now.

Relay or K40 module? If you think relay, do you know which relay number or could it match the fuel pump relay in the trunk. I replaced it after reading last week about the dash light problems.

Forgot to say, I replaced the trunk battery for two reasons. One it was 5 years old, second, just worried about the voltage to the electrical system may have a bearing on the problem gremlins.

Do you have a way to reset the system might be worth a try.

This morning I went to the Dealer and picked up a relay in their minds. I described it as the K40 relay on the K40 module.

They said the saw a relay on the K40 module for my 2003 E320 and said the fuse box was on the passenger side of the engine.

I expected to see what they described but NO. I have a fuse box on the drivers side of the engine and the cabin filter on the passenger side.

I found some pics on the internet that show fuse boxes some on the left side and some on the right side.

Is there anyone here that can tell me where the K40 relay is on my 2003 E320?

It was suspected that the K40 relay might be a problem but I can't find the exact relay to change.

This photo is of my 2003 E320 engine fuse box. Is the K40 relay or the K40 module here? Thenks

I replaced the brake light switch late tonight and the error codes are gone and so all is well again.

But there is one thing I wish someone could help ID the K40 relay or module in my 2003 E320. The internet says the engine fuse panel is on the passenger side, but that's not true.
My 2003 E320 has a fuse panel on the drivers side on the engine. Does that make my E320 a late 2002 or an earlier 2004?

Does anyone know for sure?

I have a set of Mercedes workshop on CD somewhere but for the life of me this week I cannot find them so I was fixed online for help.

Last post about this,

I looked up the bill where the Mercedes dealer replaced the '"Stop light Switch" 15 months ago. it lasted a little over 13,000 miles, but that's not good enough.
I put that thought about solving the problem back in the drawer because the switch was installed new less than two years ago.

My point being, don't trust what was recently done to still be in working order.

I hope my problem and solution could help another.