I've now researched this subject to death but can't find anyone that's solved the problem for the pre-facelift W164?

So I have the hood open warning message on the dash


I've tried replacing the switch with a brand new one


I've checked the release handle is correctly seated in the closed position


I've cleaned and checked the front SAM for water damage. None of this has made any difference?

The only solution I've seen for the W164 was to check the position of the red release handle. However, this was for a facelift W164 and for my 2006 320 CDI I can't see how the position of the handle can make any difference other than prevent the bonnet from staying shut? There is no electrical connection to the release handle and I have tried closing the switch manually to see if the light goes out - nothing!

Could it be related to another electrical fault?

Running out of ideas with this one now - can anyone suggest anything else to check?

The tailgate is controlled by the rear SAM. Close all doors and the tailgate. Then lock the truck with the remote.

Do the tail lamps blink? Regardless, try and open the tailgate manually.

My problem is with the hood/bonnet not the tailgate?

However, yes the tail lamps blink when locking with the remote.

Sorry, I misread your post.

Is the message constantly on or only when the eng. is running?

What does the owner's manual say about this issue?

The message is constantly on when the ignition switch is in position 2 or with the engine running.

The only info I can find in the Owners Manual is as follows:

AJC, give me an hour or so and I'll check a few things.

The warning says door open, you sure it's for the hood switch?

Great catch paisano. Better eyes than mine.

AJC, could you please clear this problem up?

I think that's just the older graphics on this early W164?

If one of the four doors were open the graphic changes to show which one. For the bonnet and tailgate you just get either section coloured in.

But they aren't colored? And the message still says hood/gate or something, the 164 isn't that antiquated.

Just to clarify....



Everything open - doors, hood and tailgate



Rear doors and tailgate closed - tailgate graphic hasn't changed so suspect microswitch has failed in tailgate lock?



Everything closed - message changed from 'Doors open!' to 'Door open!'


In all pictures the headlights and front grille appear slightly coloured in, which I assume indicates the hood is open?

Perhaps someone with the same car and year can check their graphic to compare?

Your are going to have the truck scanned for codes.

Here is the functional diagram for Keyless Go Central locking and note that the hood ATA Sw. S62 is controlled by the rear SAM, if that is the door that is indicated.

You also have to consider the fact that you have previously replaced both front door locks.

https://mbworld.org/forums/m-class-w...ml#post7270173

And if you just left the tailgate open, what would the message look like?

I'd bet you have faults in the cluster or front/rear SAM that will guide you further. That seems more like a faulty cluster to show that diagram with no part of the vehicle lit/open.

Hmm. Hail mary, but maybe the gas cap door?

Thank you for all the advice.

I visited an indie with STAR this morning and had the truck scanned for faults. Plenty of stored codes in the system that have now been removed.

Hey presto - error message has disappeared.

It was annoying to learn the car still had old fault codes logged having recently paid other garages with STAR to remove them on two separate occasions.

My ownership experience thus far is highlighting the importance of a local trusted garage that can attend to those jobs requiring STAR diagnostics without ripping you off each time! A big thanks to Gareth of ACE Engineering Ltd, Billingshurst for great service.

Moral of the Story: You don't need STAR or a dealer to remove error codes. I have an older Actron CP9180 scanner and it does the job perfectly.

Good that you got it resolved.

I think that depends on what faults are present? Whilst other OBD II readers are perfectly adept at communicating with most of the common modules, AFAIK STAR is the only system with a multiplexer that will read all available modules on the car?

Not true. There are many scanners other than STAR that will read every module. Here is one of them.

Well, I checked with Actron (now owned by Bosch) and it turns out that my scanner won't read everything. In fact, none of their scanners do. Here's what I got from them: