Testing vacuum pump-central locking system
 

I have a 2005 SRT and when I use the key fob to lock (or unlock) the car the only lock that works is the driver side. The hatch, the gas door and passenger door remain open. Also the switch on the console does the same thing. I pulled the vacuum pump of the central locking system from the back of the car. My question is does anyone know how to test it? The three little plastic nipples (attached to yellow lines are all supposed to emit air when locking correct?? I took the housing that holds the 2 lines off and hit the lock function on the key fob. Only one of the nipples emits air. I don't think I have a vacuum leak anywhere ...I really think it's a bad pump, but before I shell out $400 for a new pump I would like to be able to test the one in my car. I've checked fuse #9 in the fuse box...it's good. Any help bench testing this unit would be appreciated. vr, Lee

Re: Testing vacuum pump-central locking system
 

Did it just fail all at once or is it a problem that that has got progressively worse?
The lines can get brittle and break the most common is the hatch lock on coupes.
You say you took the housing off that holds two lines, do you mean the manifold with three lines? I am sure that it is fed underneath by one port for air and one vacuum port.
If you took of the three hoses from the manifold each one would blow or suck. Only by doing this would you know that they at least were working. In which case you probably have broken air lines somewhere.
Here is some pictures.
https://www.crossfireforum.org/forum...tml

Re: Testing vacuum pump-central locking system
 

180 thx. I just happened to notice that my car was not locked on the passenger side one day about a week ago. Yes I do mean the manifold with three yellow lines. There is a black clip that hlods it on to the main body. When you say they would all blow or suck do you mean they all would do the same thing (blow perhaps if I went to lock or suck if I were to unlock) Or are they independent and one might blow while two might suck for example? I jus made the assumption (maybe erroneously) that all three would do the same thing depending on whether I was locking or unlocking the car. I really hear no hissing noises that I keep reading about which may or may not mean anything. However when connected the driver door locks and then the pump times out after 10 or so seconds. Thanks much!

Re: Testing vacuum pump-central locking system
 

180 I just re-read my post. I want to make it very clear (the question I'm asking). If I were to hit the lock feature on the key fob would all three lines suck? I have to assume they would (or perhaps all 3 would blow)...anyway they all would do the same thing for a given function correct? Once again thanks for the info. I've been a member here actually for over 4 years but rarely if ever post, but really need expert help on this one to make sure I do it right.

Re: Testing vacuum pump-central locking system
 

I have never looked at this unit, so everything I say is based on assumption.

Is the manifold divided into two sections?
A pump will suck on one side and blow on the other, just like a vacuum cleaner. It is possible that this suck and blow system is used, that way it does not have to blow so much air to operate two locks and uses the other side to suck the other two locks.
In this case one port will suck and the other two ports will blow. On the other cycle that one port will blow and the other two suck. Locking would be done by vacuum on two locks and air pressure on the other two. I would think that the two door locks are using air pressure and vacuum the same way. They are similar, while the hatch and gas cap are different locks.

If the manifold is not divided then all three ports will either blow or suck.

One air line must be teed off somewhere, I suspect the gas cap and hatch locks. This would be the line that is separately operated if there is a divided manifold, I guess. In which case the latch and gas cap would fail at the same time if that hose broke. But no one has mentioned that, so it's just a guess.

If you test for blow and suck by removing the hoses from the manifold you could find out what the system is doing and possibly find the fault.

Have you opened the unit? There may be a leak inside it to one or more ports.

Re: Testing vacuum pump-central locking system
 

No I have not opened it...I will do that tomorrow. I'm absolutely amazed at the cost of this piece! I'm going to research a little more and see if I can find a schematic on it. Thx for your info! vr,

Re: Testing vacuum pump-central locking system
 

If u can't find a schematic for it, search for Mercedes pse schematic. I think I have it on my computer but I'm not home right now.

Re: Testing vacuum pump-central locking system
 

Still not fixed. I voltage tested the #2 and #4 cavity on the CLP/SSM and both had 12 volts of current. So if I read the diagnostics portion of the repair manual correctly it is saying replace with a new CLP/SSM and all should be good. I still want to check the vac line on the bend at the hatch to make sure there is no leak there. If there is a leak I should be able to hear it, right??

Re: Testing vacuum pump-central locking system
 

Have you tested the ports for air pressure and vacuum?
If they are OK then the problem lies in the lines or locks.

Re: Testing vacuum pump-central locking system
 

attached from MB

Re: Testing vacuum pump-central locking system
 

:( Looking at this diagram (Thanks Rekcah) it shows the module either blows or sucks all three at the same time so if when testing it, all three should do the same thing. Looks like a module not doing what its supposed to (to me). Search for a less expensive one they are out there. :(

:confused: One last thing! Did you try hitting the lock/unlock button twice? I understand (from somewhere deep down in my grey matter) that you can set it up to lock/unlock in stages. Anyone else remember this or have a different take on this? :confused:

Re: Testing vacuum pump-central locking system
 

Could you explain how your reading of that diagram explains the blow or suck cycle? The two doors are on opposite ends of the manifold, so one could be suck and the other blow, this may help if you want to open the doors on a separate cycle.

That top part is a manifold and there are two ports at one end and one at the other, this is a hint that the ports operate separately on the pump. I cannot be sure of that but the operation would be quicker using a smaller pump. I have asked the OP to confirm how but there is no response on this question. Sometimes answering a question can help with the solution.


The remote can be set up in two modes, all doors and hatch or driver door with one push and the passenger door and hatch with a second push.

Re: Testing vacuum pump-central locking system
 

Well not sure how to answer this but here goes. When I tested the CLP/SSM only one line responded at all with pressure. If there was indeed a vacuum on any it was negligible. Yes I know about the key fob and that you can set it up two different ways. That is not the problem. I have not yet opened the unit. When I drive the car the drivers door will lock like it should however the other door does not lock (ie when reaching 5 to 10 MPH). I can hear the pump run for a while then it stops after time out. Pushing the key fob I can get the driver door to lock and unlock but not the passenger door the fuel door or the rear hatch. Those 3 remain unlocked no matter what.

Re: Testing vacuum pump-central locking system
 

If you look at the diagram you will see that the center yellow line goes to the drivers door. If you can disconnect the other two lines you should be able to see if there is a vacuum or pressure when you select lock or unlock. If you lock the doors and either blow or suck on each line That should lock or unlock the other door and trunk and gas door. It should also show if one of them is leaking. Good luck

Re: Testing vacuum pump-central locking system
 

:) 180, It didn't look possible for one to suck while two were blowing from that diagram. The two stage operation comes from them being separated (left front door and passenger/hatch/gas route by that piping from the module). There could be another solenoid internally between the sections allowing one to suck and the other section to blow, but I seem to remember reading in the forum that when troubleshot by another forum member, the cycle was one (driver) sucking on one push, all others not doing anything, to the second three sucking on the second push (setup to drivers door opening on one push and the rest on pushing the button twice), to all of them sucking or blowing at once when configured to that configuration of everything opening at one push of the button. If he isn't getting any sucking/blowing from that rear section, I think he needs another module. Remember there are cheaper ones available than from chrysler! :)

:cool: Just my $0.02 worth. :cool:

Re: Testing vacuum pump-central locking system
 

All the doors lock with a vacuum and unlock with pressure. Not both at the same time

Re: Testing vacuum pump-central locking system
 

Ok I've tried the CLP/SSM testing as best I can tell it is malfunctioning. After about 4 hours of research I found a ned MB unit for about $390. If my original pump is working it is negligible (except for the drivers door). When I get the new pump in I'll post the results. Thx all

Re: Testing vacuum pump-central locking system
 

Replaced the CLP/SSM...still no luck. I've also checked both relays under the main fuse box top. The black one is TYCO 002 542 21 19 the yellow one is TYCO A002 542 14 19. Both are working, you can actually feel and hear them click when you depress the lock/unlock on the key transmitter. The last part I guess I can change is the SKREEM then it will be dealership time (which I absolutely despise because for every problem they have fixed they have caused another). If anyone has any other ideas I certainly would appreciate them. Thanks!

Re: Testing vacuum pump-central locking system
 

It sounds like a leak in one of the lines.

Re: Testing vacuum pump-central locking system
 

Ok finally found the problem. The driver side door lock mechanism is malfunctioning. Replaced with a new unit and all is well.

Re: Testing vacuum pump-central locking system
 

Strange, because it was working OK and the other locks were not. As the others were not working and assuming that not that many would fail all at once I can see why this would be a hard problem to diagnose.:confused:
Live and learn I guess.

Re: Testing vacuum pump-central locking system
 

Boy you're telling me (hard to diagnose). I've got the whole car ripped apart. Now I have to just put it all back together. I've thought about selling this car several times but just can't bring myself to part with it. This little SRT just really runs great and there's not a bunch of them on the road. I'm extremely happy with the MPG for the power it has. My neighbor is ticked off because he can't stay with me at all in his Mustang GT.

Re: Testing vacuum pump-central locking system
 

This diagram is the same for coupe and roadster? I think not.
In my cars is also vacuum lock storage. (2x doors, trunk, gas door, storage lock).
Anybody have vacuum diagram for roadster?

Re: Testing vacuum pump-central locking system
 

The only difference between the coupe and roadster is the central console locking.
I believe this tees off the line to the gas door, but am not completely sure.
No, I have no diagram showing the console lock.

Re: Testing vacuum pump-central locking system
 

The storage lock is just a teed extension as ala_xfire says, and only locks when the whole car is locked. A simple fact that I forgot in my first answer. Dummy that I am.:(
https://cimg3.ibsrv.net/gimg/www.cro...4e58d9989e.jpg

https://cimg4.ibsrv.net/gimg/www.cro...4bf78cc17f.jpg

https://cimg5.ibsrv.net/gimg/www.cro...d90528c661.jpg

https://cimg6.ibsrv.net/gimg/www.cro...712172232a.jpg

Re: Testing vacuum pump-central locking system
 

From vacuum pump: 2 pipes for doors and trunk, 1 pipe for gas door and storage lock.
When normaly gas door and storage lock are closed/opened?
This is strange that storage lock and gas door are closed/open in the same time.
In my car this was not work ok (gas door always closed, I must opened from trunk).
But I fix this problem. In vacuum pump is electric valve. Normaly always open only for trunk and doors (gas door and storage closed). I make that all open.
Now doors, trunk, gas door and storage are close or open in the same time.
Anybody can explain how it works oryginaly?

Re: Testing vacuum pump-central locking system
 

Re: Testing vacuum pump-central locking system
 

With the original key fob that came with the car the locking function was preformed on all the locks with one push of the button and was accomplished with vacuum. To unlock the car you had two options: one push of the button would unlock only the drivers door and all the other locks except I think the gas cap would remain closed. This was accomplished with pressure. The second option was one push of the button would unlock all the locks at the same time, also accomplished with pressure. You could program your key fob either way, which was explained in the owners manual as global unlocking.

Re: Testing vacuum pump-central locking system
 

Understood ;) but I still thinking that too big brain designed this vacuum lock.
Probably it did not work ok becouse in my car I not have oryginal remote control.

Re: Testing vacuum pump-central locking system
 

It works just fine so long as water does not get into the pumps electrics.
Your car seems to have a lot of problems unfortunately.

Re: Testing vacuum pump-central locking system
 

My electric pump have 3-5 cm styrofoam base, I hope that will be no problem with water (and car is all time in garage, I only use it for fun).
Car have many problems becouse was cheap but every problems are trifle, I like work in garage, for me it's better than crossword puzzle and most I can fix myself with your help ;)

Re: Testing vacuum pump-central locking system
 

:) You have a GREAT outlook on life (at least in regards to external car things)! I must comment on your comment @ ("My electric pump have 3-5 cm styrofoam base, I hope that will be no problem with water"). In this case nothing can prevent problems with your central locking module when water intrusion comes into contact with this module. I stand corrected, if you totally SEALED (which cannot be done) this part you can prevent moisture problems BUT you may have forgot this module relies on an air pump! A pump like this NEEDS an air intake, hence any sealing of the unit being impossible. Check for moisture/water there, too many have found out the longer it sits there, the more costly to fix! :)


:) It may be something else, but checking for this issue (which has caused far too many of the same problems you experience) is FREE! It could save you a lot of $ (in your funds). If that module is even slightly damaged, it could explain your problem. Water intrusion is a known problem with this component. Good luck!

Re: Testing vacuum pump-central locking system
 

Thank you :D
Offcourse, this is not possible for totaly sealed this vacuum pump but I have idea.
Check photos. Behind arrow is many free space above floor.

Re: Testing vacuum pump-central locking system
 

:) I suppose you can move it higher? Never heard or seen anyone else do that before. Just be careful with routing the wires (and most importantly) those fragile air lines. I have read they get a little brittle, the older they get. :)

Re: Testing vacuum pump-central locking system
 

It's only idea but I think will be no problem for move it.
I'll be watching water level in trunk ;)

Re: Testing vacuum pump-central locking system
 

I know it's been six years, but thanks for posting the Central Pump line routing diagram.

Re: Testing vacuum pump-central locking system
 

I added more details in post #25 if they are any help.