Temporary Disabling Central Locking

[Tom Evans]

I need to temporarily disable the central locking system in my son's 1984 300D. He is about 300 miles away and it will be about two months before I can go see him and work on the central locking system. The system is operating erratically and he really only needs to lock and unlock the driver's door.

I remember two check valves near the oil filter housing. One was a 1 in/2 out check valve that was gray and yellow. If I remember correctly, this check valve is for the climate control.

There should be another 1 in/1 out check valve for the central locking system in the same vacinity. Does anyone remember what the color is for this check valve, black/white or black/blue?

My thought is to have my son disconnect this check valve on the input side and plug the hose until I can work on the system.

Any other suggestions?

Thanks.

Block the two big yellow lines going into the firewall.