SLK PSE Vacuum Pipes

[Tim Soles]

Hi,

My 2000 SLK 230 has suffered from the usual problem of damp affecting the PSE unit in the boot.

The interior light had a mind of its own, the central locking was eratic and often locked and unlocked whilst driving, and I had occasional false alarms.

Having taken the unit to bits, the corrosion was very slight with just some damp in the white electrical connector causing the pins to slightly corrode. I've carefully cleaned it up and all seems well at the moment.

However, I would like to turn the unit upside down (as on later models) to stop more water running down the wires and into the unit. The wires are long enough but the 3 yellow vacuum pipes need extending. Can anyone tell me if they have done this and what pipes they used for the extension? Vacuum pipe is advertised on eBay but I am not sure about sizes and how to connect to the existing pipes.

Cheers, Tim

[television]

I am sticking my neck out here, but I used extensions by using pipe from a indoor fish shop that is used for aerating the tanks to repair damaged comfort seat pipes.

When warm, this pipe only need to slide over the join 20mm.

By the way before you put you PCB back, pop into Maplins and get a can of PCB lacquer and spray the board twice

[Bazzle]

I have done this too. Posted a how to here;
http://www.benzworld.org/forums/r170-slk-class/1270676-pse-removal-refit-check.html
I used plastic pipe that slid over but only as I had it lying around. Next time I would just use small bore rubber auto vac hose. Fish tank pipe is ok but in longer lengths may suck in.

Bazzle

[television]

I have done this too. Posted a how to here;
http://www.benzworld.org/forums/r170-slk-class/1270676-pse-removal-refit-check.html
I used plastic pipe that slid over but only as I had it lying around. Next time I would just use small bore rubber auto vac hose. Fish tank pipe is ok but in longer lengths may suck in.

Bazzle

Thank you Bazzle for pointing that out, fish tank pipe is not as hard as the MB version but I doubt if it would suck in, its quite thick.

Every hand spray cleaner bottles for kitchens and bathrooms has several sizes of pipe and one way valves, these valves are perfect for testing seats etc from an external compressor

[Tim Soles]

Thanks for the link Bazzle - excellent Post.

I thought I had fixed my problem but when I took the car out today the interior light came on everytime I went over the slightest bump, and the central locking was also trying to unlock from time to time. Is this definitely the PSE?

The board looked clean and the only damage I could find was in the white connector. It's difficult to clean the pins in the connector, but I will try again next weekend. Presumably, if the connector pins are badly corroded there will be no choice but to replace the PSE?

I will also give the board a gentle rub - is WD40 OK for this? I will get some PCB laquer for future protection and some vac hose so I can turn the unit upside down.

Tim

[television]

Any non drying switch cleaner (maplins) will take away any white corrosion from the connectors.

You can get dry soldered joints on these boards, looking through a good magnifying glass you can see if there are any where there are dark rings around any of the joints. Its best to blanket solder the whole board

If you cannot do this I could do it for you FOC.

[Tim Soles]

I ended up replacing the PSE unit this weekend, largely because of the continued alarm problems which was causing upset with my neighbours.

Incidently, my local MB Stealer said that MB had none in stock in the UK and they were on back order with an unknown delivery date. However, he was able to tell me of another local dealer who had one in stock - it only cost £373.65!!!!!!

The good news is that the false alarms and door locking/unlocking problems seem to be resolved. The bad news is that the interior light is now staying on! Having said that - if I start to open the window the light goes off!

I am guessing the current drain for the window is enough to kick-start the interior light dimmer.

I am open to any suggestions, but I am wondering whether it is a problem with one of the contacts that plugs into the PSE. Would some kind person who has access to a wiring diagram be able to tell me the colour of the wires that plug into the PSE that control the lighting circuit? That will help me to identify which pins might be causing the problem (if that is the problem).

My car is a 2000 facelift model 170.449. The PSE unit is part number 1708000848 - it has two big connectors at one end (one black, one white, and two smaller connectors at the other end.

Cheers

Tim