2009 Sprinter keyfob not opening/locking

[WildeSwimming]

Hi - not sure if this is the right section in the forum.

hi I have a 2009 mercedes sprinter (ex-ambulance, 518 3.0 CDI) that I bought at auction today. The van was open when I drove it away (the key works in the ignition no problem). However when I stopped and wanted to centrally lock the van, there is absolutely no reaction. I've checked the battery and it's ok red light on fob etc. I brought the key to a shop (Timsons) to ask them to check the fob and they said there's no infrared (?) signal coming from the key. Can you help please?

 

[SprinterBR906]

Hi

The key does not actually use infrared for central locking. That’s only for high comfort vehicles, which being an ambulance will not have.

The keys actually use radio waves for the central locking. This can be checked using a frequency detector.

Does the central locking work from inside the vehicle using the button on the upper control panel?