SL/R129: central locking system
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Joined: Aug 2018
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1998 r129
central locking system
my 98 sl500 central locking system quit working. replaced pump with another, yes it's used but from a reputable source and tested. now remotely doors lock and trunk pops open but won't unlock doors or unlock fuel door or unlock between seat storage. doors and storage will unlock manually with key. turn signals light when remote pressed so there is communication between car and remote. any help appreciated. curious as to where vacuum chamber is located and which systems work on vacuum and which work on pressure.
Banned
Joined: Jan 2006
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From: Atlanta, unfortunately
'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
All locking elements work on both pressure and vacuum. If your turn signal lights lamp once or three times depending upon whether you are locking or unlocking the vehicle, then it seems likely your pump is defective.
Banned
Joined: Jan 2006
Posts: 1,982
Likes: 393
From: Atlanta, unfortunately
'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
All locking elements work on both pressure and vacuum. If your turn signal lights lamp once or three times depending upon whether you are locking or unlocking the vehicle, then it seems likely your pump is defective.
I'd open the trunk lid, and I'd remove one of the pneumatic connections to the pneumatic pump located above the battery. Then alternately lock and unlock the car using the remote while placing a finger over one of the exposed ports. You should be able to discern whether the pump is able to produce both vacuum and pressure.
I'd open the trunk lid, and I'd remove one of the pneumatic connections to the pneumatic pump located above the battery. Then alternately lock and unlock the car using the remote while placing a finger over one of the exposed ports. You should be able to discern whether the pump is able to produce both vacuum and pressure.
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Joined: Jun 2017
Posts: 179
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From: Austin, TX
1997 SL600, 2017 AMG GTS
