PSE Nightmare

[Dazza.ba]

Hi New member help please. I have a lovely SLK230 face lift year 2000 67k miles RHD. I have read many post re wet PSE and Alarm siren battery fail. My SLK was fine then wipers came on on their own and stopped mid screen. Forum said likely N10-3 CCU fault swapped with a used ebay and worked ok. 3 days later hazards flashing no alarm siren. Lock unlock all ok for 10 mins then lights flash again. Forum said disconnect siren so did this. Next day central locking stopped working, interior light stopped with tow light staying on permanently. Checked PSE sopping wet dried it out cleaned terminals etc replaced unit. Int light boot light working tow light now off but no central locking using key fobs or dash lock switch. Fuses 9, 24,25,26 all appear new. Paid £160 for used PSE fitted it no change still no locking and tow light inoperative. My question is: How can i test if replacement PSE is working? Is there a simple way of testing the connectors to it they are okay they did not look too green? Is it necessary to pair or sync the replacement PSE to the car? Your help would be very much appreciated thank you for listening. Daz

 

[grahamcol]

Welcome from a fellow SLK owner. Great cars! When l first read this l instantly thought alarm siren. However you disconnected that and you still have issues, so l can't suggest much else to help you unfortunately. Good luck and please let us know how you get on with this.

 

[peterws1957]

I presume that your SLK will have 2 batteries, starter battery under the bonnet and consumer battery in the boot. The symptoms you are describing are suggestive of a low consumer battery which can throw up all sorts of problems. Have you checked both batteries? Can you hear the pse pump operating when the car is switched on? (note that used pumps on eBay etc are sometimes sold because they are faulty)
If everything checks out (no leak in the lines to the doors) I'd be removing the pipe connection and feeling if the outlets are working. If the boot soft close and other consumers operated by the pump are working I doubt if it's the pump that's faulty. Also any hissing sound from the boot lock area which is a common fault with these caused by cracks in the plastic lock mechanism.

 

[ajlsl600]

I understand, memory withstanding that plastic manifold of pse suffers from cracking, if so limited or no vacuum. As above unlikely if soft close works? If system leaks I believe pump will run until timed out putting more wear n tear on pump. Put pump, if working on top of 10 mm polystirene in a plastic zipper bag helps keep it out of water... If car outside check boot weekly and do any repairs req to keep boot dry, also check all Yr earth's.

 

[Blobcat]

I presume that your SLK will have 2 batteries, starter battery under the bonnet and consumer battery in the boot. The symptoms you are describing are suggestive of a low consumer battery which can throw up all sorts of problems. Have you checked both batteries? Can you hear the pse pump operating when the car is switched on? (note that used pumps on eBay etc are sometimes sold because they are faulty)
If everything checks out (no leak in the lines to the doors) I'd be removing the pipe connection and feeling if the outlets are working. If the boot soft close and other consumers operated by the pump are working I doubt if it's the pump that's faulty. Also any hissing sound from the boot lock area which is a common fault with these caused by cracks in the plastic lock mechanism.

I don’t believe R170 SLK’s have 2 batteries

 

[grahamcol]

One battery and no soft close.

 

[Dazza.ba]

Hi thanks for your replies. Car has only one battery and no soft close i think? When the PSE is connected the interior lights work and demister and the lock and unlock flasher lights work when using the key fob remote but the doors locks do not pop up or down. No wirring or hissing sound from the PSE pump. Is there a way of testing the wire connectors to the PSE or the pump itself? Thanks D

 

[Dazza.ba]

Also does anyone know a reasonably priced independent MB specialist in the southwest?

 

[NJS5]

Welcome Dazza.ba

How far West? Prestige Car Service in Horndean are excellent.

Good luck.

NJSS

 

[John77]

I had the same problem around 6 years ago. A senior member who is no longer with us (Television) told me to send him the PSE unit and he would fix it for me, postage only. 3 days later it came back fixed, and he had taken photos of the internal circuit board which had deteriorated with the water. He rewired it for me, and all worked. If you are going to get another PSE unit, it may be interesting to open it up and see. Also, he extended the wires so that it could be reinstalled upside down to stop this happening again. You also need to extend the vacuum pipes. I used rubber vacuum pipes as the MB ones are not flexible enough. I have just looked for the post but cannot find it.

 

[Dazza.ba]

I had the same problem around 6 years ago. A senior member who is no longer with us (Television) told me to send him the PSE unit and he would fix it for me, postage only. 3 days later it came back fixed, and he had taken photos of the internal circuit board which had deteriorated with the water. He rewired it for me, and all worked. If you are going to get another PSE unit, it may be interesting to open it up and see. Also, he extended the wires so that it could be reinstalled upside down to stop this happening again. You also need to extend the vacuum pipes. I used rubber vacuum pipes as the MB ones are not flexible enough. I have just looked for the post but cannot find it.

Hi thanks for your tips much appreciated. I removed the alarm siren and bought another £200 used but dry PSE pump and connected it. Bingo everything worked again central locking int lights demister and with No tow alarm on. I thought i had cracked it. Next morning get in car tow light comes on and wont go off even with ignition key out. No water in PSE pump no corroded connector pins i am stumped as to the cause ? Question could the missing alarm siren cause this? Can the tow warning light be deactived without affecting other electric functions? Please help if you can i love this car and want to keep it.

 

[ajlsl600]

If you changed pump and it worked for a day its faulty wiring or faulty badly connected (corroded control) unit and or any relays does the car start easily ie battery good and has water there previously corroded any earth posts related to the pump
Have you had the car on decent diagnostics, xentry or icarsoft.

Hi thanks for your tips much appreciated. I removed the alarm siren and bought another £200 used but dry PSE pump and connected it. Bingo everything worked again central locking int lights demister and with No tow alarm on. I thought i had cracked it. Next morning get in car tow light comes on and wont go off even with ignition key out. No water in PSE pump no corroded connector pins i am stumped as to the cause ? Question could the missing alarm siren cause this? Can the tow warning light be deactived without affecting other electric functions? Please help if you can i love this car and want to keep it.

 

[Dazza.ba]

If you changed pump and it worked for a day its faulty wiring or faulty badly connected (corroded control) unit and or any relays does the car start easily ie battery good and has water there previously corroded any earth posts related to the pump
Have you had the car on decent diagnostics, xentry or icarsoft.

Hi Aj thank you so much for your response. Last night i discountected the pump terminals connectors and cleaned them again with circuit spray and reconnected it this morning all working again as it should be. No signs of damp in new pump or block terminals but my wiring loom and block connectors were immersed for s while but not too corroded. I guess i will have to wait a few hours to see if it recurs. I was worried having spent £200 on a used pump that if it was faulty i needed to return it quickly for a refund. If its likely to be the wiring loom or external connectors i can keep the pump and look to address them. I cant thank you enough for taking the time to respond. Any other tips would be gratefully received.

 

[ajlsl600]

Grand. See how behaves for a few days. Modern benz and prob others have become very temperamental where electrics are concerned, especially if water has been added. Sensors, control units are often required to report within predetermined perameters and get psd off when readings are not so. Throwing all sorts of reports. Codes. The one I love. Response from? Is not with limits or the like. Unless the car is new or near. And even then such reports can hav u chasing ur own arxx for ages. Hope ur sorted