You might need to programming the remote. Their should be instructions in the users manual. You're remote could also be need new batteries.
Open the keyless remote and you will see the battery take it out and replace it with the same size.
Check the batteries in the remote with a volt meter.
The positive ( + ) side of the batteries faces down
I have just replaced some batteries in my 2001 ml 320 keyless remote and its not activating my security system. How do I get the remote to work again? Please help!!!
The keypad doesn't take batteries , the remote takes a battery or batteries
buy a new one
Cut open the remote with xacto knife , unsolder and replace the battery.
Each remote takes ( 2 ) # 2016 batteries , they are coin style 3 volt lithium batteries
The batteries may be dead on the remote.
You can change a battery for Passat 2003 remote controller as follows. - turning with small flat screw driver from small hole separate two parts . - separate parts where buttons are with screw driver - replace battery, type CR2032 3V - assemble parts together I had no need for any reprogramming. Remote controller started to work just by replacing a battery.