1991 Mercedes 500SL Issue with the seats only moving forward PLEASE HELP!!!

[ron59b]

Good evening all

My 1991 500SL (94,000 Mmiles) is new to me and I am working the bugs out. Both of my seats will only move forward when using the adjustment switches on the doors. Weather the switch is set to move forward or backwards, the seats move forward. I am lucky that the memory function has one number that is set to move the seat partially back, but not completely.

I have read on the forum about a relay box under the seats. Can someone provide more information on what to check? Is there a DIY method/ hack to move the seats back? Again this happens with both seats. When moving some of the other seat adjustments, the seats will occassionally move the bottoms back.

Thanks for your time reading my rant. Any assistance will be appreciated.

Thank you

Ron
(Richmond, VA)

[Diseasel300]

I'd suspect the switches in the doors over the relay box. Since the seats move back when you recall a memory position, the relay box works (or else the seats still wouldn't move back). Not familiar with the R129, but if they're set up like the 126/124 switches, there's a ton of little parts inside that all have to move together to give the proper function. The grease they used inside gums up and prevents contacts from making or moving properly.

[ron59b]

Thank you for the response. Where does the grease and dirt build up. Does accessing and cleaning ymthe area help? Does the switches need to replaced or serviced?

[ron59b]

Do I need to clean the door switches or the seat motor and electrical?