Keyless Start Works but Keyless Entry Doesn't

[rockits]

I have a 2005 S211 E55K with Keyless Go and the Keyless Start works perfectly fine as the car starts/stops OK on the gearshift button. However, none of the door handles work to lock or unlock the car. I have had it before on previous 211's where it was one or two handles that had to be replaced but never all 4 on both lock or unlock. I'm wondering if maybe due to the current Keyless thefts that a previous owner could have disabled or coded out the Keyless Entry option for security reasons.

I'm just going to be selling the car soon so going through and making sure everything is working and the car is as good as can be. I never use Keyless Entry so the issue has never bothered me in my ownership as I never use it anyway. I've tried new fob batteries and checked fuses so they all seem good. Tried both keys and both have new batteries. Both keys work for Keyless Start and the remotes unlock/lock and start the car. Just only the Keyless Entry feature is not working for unlock or lock on the handles. Seems odd that all 4 handles are faulty for both lock and unlock.

Has anyone ever had that before please? Was thinking it could be the antenna or control module but seems unlikely as the Keyless Start feature works perfectly fine. I get no errors or malfunctions come up.

I'm half of the mind to leave it as is, to make the car more secure in that sense, as nobody could unlock the car with any scanners or repeaters currently. I know some people have decided to disable these Keyless Entry features or pull the fuse or code the feature out because of security concerns.

Any thoughts or opinions are very welcomed and much appreciated.

 

[Bigdrew]

I have a 2005 S211 E55K with Keyless Go and the Keyless Start works perfectly fine as the car starts/stops OK on the gearshift button. However, none of the door handles work to lock or unlock the car. I have had it before on previous 211's where it was one or two handles that had to be replaced but never all 4 on both lock or unlock. I'm wondering if maybe due to the current Keyless thefts that a previous owner could have disabled or coded out the Keyless Entry option for security reasons.

I'm just going to be selling the car soon so going through and making sure everything is working and the car is as good as can be. I never use Keyless Entry so the issue has never bothered me in my ownership as I never use it anyway. I've tried new fob batteries and checked fuses so they all seem good. Tried both keys and both have new batteries. Both keys work for Keyless Start and the remotes unlock/lock and start the car. Just only the Keyless Entry feature is not working for unlock or lock on the handles. Seems odd that all 4 handles are faulty for both lock and unlock.

Has anyone ever had that before please? Was thinking it could be the antenna or control module but seems unlikely as the Keyless Start feature works perfectly fine. I get no errors or malfunctions come up.

I'm half of the mind to leave it as is, to make the car more secure in that sense, as nobody could unlock the car with any scanners or repeaters currently. I know some people have decided to disable these Keyless Entry features or pull the fuse or code the feature out because of security concerns.

Any thoughts or opinions are very welcomed and much appreciated.

Hi was it working previously

 

[rockits]

Hi was it working previously

It has never worked in my ownership which is why I was thinking maybe it was coded out or disabled previously.

 

[Bigdrew]

It has never worked in my ownership which is why I was thinking maybe it was coded out or disabled previously.

I am sure there is a way to switch it off using the key fob

 

[rockits]

I am sure there is a way to switch it off using the key fob

Yes. I know you can double press the lock button on the remote when locking to disable it for that session as it were. I'm sure it could be coded out or disabled permanently though.

 

[Bigdrew]

Yes. I know you can double press the lock button on the remote when locking to disable it for that session as it were. I'm sure it could be coded out or disabled permanently though.

It was just a thought incase you didn’t know about that i don’t know if the keyless entry will use a fuse or a relay

 

[rockits]

It was just a thought incase you didn’t know about that i don’t know if the keyless entry will use a fuse or a relay

Thank you and much appreciated on all your thoughts.

Yes, there are a couple of fuses related that I've checked. Not sure about relays. I might see if I can find the previous owners details to see if they ever coded it out or disabled the entry aspect.

 

[Will]

Does it work from the tailgate handle?

 

[rockits]

Does it work from the tailgate handle?

Good point. Yes it does actually. Just not from all 4 doors oddly. The boot triggers the central locking to open on all 4 doors keyless no problem.

I didn't think one faulty handle affected all 4 doors but wondering if maybe it could do. I'm sure when I have had individual handles fail before on previous cars that it only affected that door and the others all worked OK.

I'm also wondering if any coding could code out the keyless entry on the doors but not the boot. That would seem odd as a potential thief could still open the boot with a scan tool/kit that would in turn open all the doors.

 

[Will]

I doubt it’s been coded out, either you have four faulty handles or a wiring/other issue.

It’s quite possible the handles are faulty if they’re twenty years old and not been previously replaced - you could simply remove one to test (literally takes a few minutes and a torx driver)

 

[rockits]

I doubt it’s been coded out, either you have four faulty handles or a wiring/other issue.

It’s quite possible the handles are faulty if they’re twenty years old and not been previously replaced - you could simply remove one to test (literally takes a few minutes and a torx driver)

Yes, agreed. I'll take one out and see what goes.

 

[rockits]

Replaced all 4 of the rear parking sensors and all working a treat now with no errors.

Only the two right ones had issues it seems but made sense to change all 4 for new ones. They all look cosmetically the same now. The old ones looked a little oxidised and jaded.

Will look at a keyless go handle tomorrow to see if I can see any issues.

 

[markjay]

AFAIK, while all 4 door are unlocked simultaneously, only the two front door handles can activate the unlocking.

I.e., the rear door handles are passive, and the two rear doors only unlock if the unlocking is activated by one of the two front door handles.

Therefore, there's no point in investigating the rear door handles, only the front ones.

To clarify, you can unlock the car by pressing the unlock button on the key fob, correct? Just not directly from the front door handle?

 

[rockits]

AFAIK, while all 4 door are unlocked simultaneously, only the two front door handles can activate the unlocking.

I.e., the rear door handles are passive, and the two rear doors only unlock if the unlocking is activated by one of the two front door handles.

Therefore, there's no point in investigating the rear door handles, only the front ones.

To clarify, you can unlock the car by pressing the unlock button on the key fob, correct? Just not directly from the front door handle?

Thanks for that. Much appreciated.

Yes, I can unlock the car fine with no issues with both remote keys/fobs. Just the keyless go entry feature isn't working. Starting the car via the top push button on the gearstick works fine. Maybe it could just be both front handles that have failed. Wouldn't be too bad to replace just those two if it were the case.

I'll take one of the front ones off tomorrow as might just be a poor contact that needs cleaning. Or maybe a dry solder joint or something on the little PCB inside the handle. I'm sure I've seen some that have fixed the existing handle in these ways rather than replacing the whole handle.

 

[OneForTheRoad]

Thanks for that. Much appreciated.

Yes, I can unlock the car fine with no issues with both remote keys/fobs. Just the keyless go entry feature isn't working. Starting the car via the top push button on the gearstick works fine. Maybe it could just be both front handles that have failed. Wouldn't be too bad to replace just those two if it were the case.

I'll take one of the front ones off tomorrow as might just be a poor contact that needs cleaning. Or maybe a dry solder joint or something on the little PCB inside the handle. I'm sure I've seen some that have fixed the existing handle in these ways rather than replacing the whole handle.

Is keyless entry listed on the data card ?

 

[Will]

Thanks for that. Much appreciated.

Yes, I can unlock the car fine with no issues with both remote keys/fobs. Just the keyless go entry feature isn't working. Starting the car via the top push button on the gearstick works fine. Maybe it could just be both front handles that have failed. Wouldn't be too bad to replace just those two if it were the case.

I'll take one of the front ones off tomorrow as might just be a poor contact that needs cleaning. Or maybe a dry solder joint or something on the little PCB inside the handle. I'm sure I've seen some that have fixed the existing handle in these ways rather than replacing the whole handle.

It’s the rubber membrane that fails, water gets in and corrodes it all.

New handle to fix. More hassle than it’s worth trying to repair these - they used to be reasonably priced from MB years ago but suspect price/availability won’t be as good nowadays.

 

[Bobby Dazzler]

AFAIK, while all 4 door are unlocked simultaneously, only the two front door handles can activate the unlocking.

I.e., the rear door handles are passive, and the two rear doors only unlock if the unlocking is activated by one of the two front door handles.

Therefore, there's no point in investigating the rear door handles, only the front ones.

To clarify, you can unlock the car by pressing the unlock button on the key fob, correct? Just not directly from the front door handle?

Not an S211 but I have a similar age Mercedes with keyless entry and touching the rear handle unlocks the car.

 

[rockits]

Is keyless entry listed on the data card ?

I'd guess so but not sure what the code is for that. Any idea what the code is please?

 

[rockits]

This is the datacard but not sure if there is a list somewhere that shows all the codes with descriptions.

 

[OneForTheRoad]

I'd guess so but not sure what the code is for that. Any idea what the code is please?

Probably easier just to put the vin code on here

Mercedes-Benz VIN decoder - Lookup and check Mercedes-Benz VIN number and get build sheet with specs.

Mercedes-Benz VIN decoder - Lookup and check Mercedes-Benz VIN number and get build sheet with specs.

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