What Is Fault Code SPN 6918 FMI 7? (Freightliner Bulkhead)

With unheard-of parts, the explanations can be more confusing than the code. Trying to figure out the explanations and what you are to do can take some time. However, it can be done eventually and you can get the part fixed.

The code SPN 6918 simply states Missing Smart Switch and it is a generic code that you will not find on many fault code lists. This switch and code are for the Freightliner M2 bulkhead module. Which may explain why you can’t find it elsewhere.

To learn about this code and other important information, just continue to read our article. It delves into this fault code to bring you as much information as possible. For an unknown code, it does come with a lot of repair steps

What is SPN 6918 FMI 7 Fault Code?


The only information we have on this code is that it has to do with one of the switches in the switch pack. This code only displays when the key and the ignition are switched to the ‘on’ position.

Don’t take DiagnosticLink’s word for anything when this code presents itself. Usually, DiagnosticLink will show that all switches have the correct parameters loaded and all are present.

The good news about this code is that to resolve it, all you have to do is update the Bulkhead module software. If your bulkhead module is at the 7.41 level, it needs to be updated to the 7.43 level.

The FMI 7 is like FMI 31, it is not much help. All this part of the code means is- Mechanical system not responding properly. All this code does is eliminate the electrical and informational components from being the source of the problem.

As of right now, this code should not cause any derate or lower performance of your engine. You should be able to drive normally until you get around to updating your bulkhead module.

The updating may have to be done by a mechanic or dealer and you should check with them first before doing it yourself.

What is An Engine Derate


We have talked about this taking place in many of our articles. But we have never fully explained it. The engine derate comes when your vehicle’s computer is lowering the speed and performance of your engine.

This action is taken when the computer sense that leaving the engine at full power, etc., will cause more damage to the motor than has already occurred. This action is seen as a beneficial one as it will prevent engine overheating and helps prolong engine life.

There are different derate levels but when you get the dreaded 5 mph derate, you can bet the farm it has to do with your emissions system or otherwise known as the after treatment system.

The derate is enacted when your engine has tried several times to clean your DPF. When unsuccessful, you will get the amber light illuminated and then you will have to become involved in the cleaning process.

Your involvement means you need to either change the mode and put more heat into your exhaust or you need to stop and do an active regen. If you don’t then the red light appears and you can go into a derate situation. That is if the engine does not shut down first.

Some Final Words

This fault code may not be serious but it is also not a very well known fault either. When it is triggered you should not lose any performance in your engine. The problem you may have is Freightliner may say that this smart switch does not exist.

It is there or you would not see the code set. The repair usually is an update of the bulkhead module but there are 19 other steps you may have to take to fix this issue. Click here to see those 19 steps. These steps are not hard to do.

Leave a Comment: