PeachParts Mercedes-Benz Forum - View Single Post

pawoSD · #7 06-26-2009, 05:22 PM

Quote:

Originally Posted by Phil

On a SD the pump in the trunk runs to produce pressure or vacuum depending on what is asked for and it keeps running for a little bit until it reaches its max limit then shuts off so if you unlock it it probably runs for 15 seconds until it reaches its limit then shuts down and restarts in the other mode due to a short.
Look at this thread and read post #13. Disreguard post #9 because I left some stuff out in it
http://www.peachparts.com/shopforum/showthread.php?t=150356

I doubt the pump runs for 15 seconds, thats waaay too long. Its easy to hear if you listen by the trunk. The pump on my car runs maybe 4 seconds to unlock, and about 3-4 to lock. Any longer and there's a significant leak somewhere and you're just wearing out the pump.

On my W124 it only runs about 1-2 seconds.....its a much quicker system as each lock has a dedicated line to a port on the pump instead of being a shared system like the older ones. They probably did this to compete with newer cars using electric actuators which are nearly instant.