96 S500 Central Locking Pump- How to install?
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96 S500
96 S500 Central Locking Pump- How to install?
Can anyone provide me with instructions on "how" to properly change out the Central Locking Pump? Of course there are several hoses etc....I got a used one that works great and it DOES still have the wires attached. However, they appear to be "thin" in some areas on the end. Also, it appears that some are attached to a "plug" that seem like they basically "snap" on by just pulling them up. These are too expensive to just assume they are as simple to change out as it may appear so I just want to be cautious with it. I attempted to pull up on one of the plugs(that the hoses are connected to) and it's on there pretty snug. Didn't want to use a pair of pliers to remove it and cause damage.(in the event a special tool is needed to remove them). Can anyone provide any assistance in this matter? Is there a DIY site that shows a "step by step" on changing these?? Thanks for any help you can provide.
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Joined: Jun 2004
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From: LI, NY
(1960) 300d, S550 AMG S500 S600 560SEL
how much did it cost you for the pump? can you post the picture? before you start pulling off the plugs connected on your old pump in the car do mark which one goes where before you start getting confuse, it is a hassle to be identifying each line if in case you have pulled it out already. then you have to manually blow on the line to see which connects to which. the pumps includes central lock for the passenger cabin, fuel door panel, and trunk lock.
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From: LI, NY
(1960) 300d, S550 AMG S500 S600 560SEL
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1994 S420
Can anyone provide me with instructions on "how" to properly change out the Central Locking Pump? Of course there are several hoses etc....I got a used one that works great and it DOES still have the wires attached. However, they appear to be "thin" in some areas on the end. Also, it appears that some are attached to a "plug" that seem like they basically "snap" on by just pulling them up. These are too expensive to just assume they are as simple to change out as it may appear so I just want to be cautious with it. I attempted to pull up on one of the plugs(that the hoses are connected to) and it's on there pretty snug. Didn't want to use a pair of pliers to remove it and cause damage.(in the event a special tool is needed to remove them). Can anyone provide any assistance in this matter? Is there a DIY site that shows a "step by step" on changing these?? Thanks for any help you can provide.
DO NOT PULL ON WIRES as other post with photo indicates.
The wire harnesses are all moly modules which plug into the pump body and are held in place with a locking mechanism.
There is a SLIDING plastic locking mechanism tab on the short side of the wire assembly which must be pulled SIDEWAYS not UP to release the wiring module. The smaller modules have locking tabs which must be released .
Good luck.
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96 S500
96 S500 central locking pump
paid $150 for it. came out of 97 S420 and had "exact" part number so it worked out great. Just so happen I saw an ad on Craigslist and guy was parting it out. It ran good but was wrecked. Got the chance to see Pump perform "all" functions perfectly. Yes, I will post pics. However, I'm still not clear exactly "how" to remove the wires yet? I followed your instructions and doesn't seem to pull off without significant resistance not sure if I'm doing it properly or if it's supposed to be that way? dont want to risk breaking anything?
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Senior Member
Joined: Jun 2004
Posts: 382
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From: LI, NY
(1960) 300d, S550 AMG S500 S600 560SEL
paid $150 for it. came out of 97 S420 and had "exact" part number so it worked out great. Just so happen I saw an ad on Craigslist and guy was parting it out. It ran good but was wrecked. Got the chance to see Pump perform "all" functions perfectly. Yes, I will post pics. However, I'm still not clear exactly "how" to remove the wires yet? I followed your instructions and doesn't seem to pull off without significant resistance not sure if I'm doing it properly or if it's supposed to be that way? dont want to risk breaking anything?
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96 S500
central locking pump pics
Sorry for the delay, here are the pics i took part#140 800 31 48 this is "exact" one that's currently in my 96 S500. Again as reiteration, I'm trying to find out proper way to remove and install. thanks for any help you can provide.
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Joined: Jun 2004
Posts: 382
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From: LI, NY
(1960) 300d, S550 AMG S500 S600 560SEL
If it is the same then you can just pull and connect one at at time and makeing sure you place each and every plug in it's proper position. MAKING SURE YOU DO NOT BEND ANY OF THE AIR LINE AND MAKING SURE YOU SNAP THE TUBE PROPERLY AND SECURELY INTO THE NEW PUMP.
ANOTHER WAY IS TO MARK BY NUMBERS ON THE PUMP AS WELL AS THE LINES USING MASKING TAPES.
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96 S500
So I can just PULL UP on these connectors? should I use pliers of some sort? They don't pull up easily by hand. Btw....pump is "identical" I've put them side by side when I purchased it.
Last edited by starky; Feb 11, 2012 at 07:49 PM.
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From: LI, NY
(1960) 300d, S550 AMG S500 S600 560SEL
NEVER USE A PLIERS, just pull them off with an assist of a plastic or screw driver placing it underneath the plug and assist while pulling it off at the point and not at the line simultaneously
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96 S500
FYI.......removed & replaced pump works perfectly as I expected. NOW...another problem. ALL of the doors unlock and lock EXCEPT the PASSENGER door. It has to be done "manually". Also it's important to note: It has ALWAYS been like this SINCE I purchased the car so I'm confident it's not any problem with the pump. OH, another question(if I may). I noticed before my pump stopped working completely it "immediately" stopped a few hours AFTER I had just come from the car wash. I've heard that water/moisture somehow gets in the floor board area and can cause it to go bad? (not sure IF this was the culprit as I've washed the car "countless" times in the 2 years I've had it without any problems) But IF this theory is true what can I do (if anything) to prevent this from happening??? I would hate to have to replace the pump again??? Any advice would be appreciated. Thanks
Last edited by starky; Feb 13, 2012 at 07:03 AM.
Senior Member
Joined: Jun 2004
Posts: 382
Likes: 4
From: LI, NY
(1960) 300d, S550 AMG S500 S600 560SEL
first on how the water could have gone inside, tell us how was the car wash done? was the car lifted and pressure washed underneath? if not water would be next to impossible to get underneath your rear seat right side. If it was pressure washed underneath, then you have to check if the rubber plugs are all in place.
on the driver side door, take out the door panel and visually check if the connections were not pinched, you can take out the lock /vacuum actuator and physically check if there are any cracks, and you can blow it with your mouth and check the function, if cracked then you can do remedial by using an plastic expoxy bond to repair, making sure that there are no holes to let the air pop out.
trace the vacuum line from the door to the pump side and see if there are any pinch or crack line that may cause the actuator to malfunction. if there is a loose air on any of the system the pump may not last long since it will keep on pumping therefore burning out the motor.
try blowing through the line which is connected from the pump to the left side / driver door actuator and see if you can manually activate the lock, if not then there is another problem.
on the driver side door, take out the door panel and visually check if the connections were not pinched, you can take out the lock /vacuum actuator and physically check if there are any cracks, and you can blow it with your mouth and check the function, if cracked then you can do remedial by using an plastic expoxy bond to repair, making sure that there are no holes to let the air pop out.
trace the vacuum line from the door to the pump side and see if there are any pinch or crack line that may cause the actuator to malfunction. if there is a loose air on any of the system the pump may not last long since it will keep on pumping therefore burning out the motor.
try blowing through the line which is connected from the pump to the left side / driver door actuator and see if you can manually activate the lock, if not then there is another problem.
