Locking issue on SL350 r230, locks only work from metal key

Page may contain affiliate links. Please see terms for details.

RattlerRattler

Active Member
Joined
Sep 26, 2013
Messages
251
Car
SL 55
Hi, I've had my 350 for a month or so and today found after driving her for a few miles and parking up, that I couldn't use the key fob to operate the door or boot locks. All other elements (alarm, courtesy lights etc) work off the fob, but no mechanical locks operate. The car starts and runs fine too.....

I was able to access the car and boot from the metal key, so got around the issue, but looking for some help.

Is this a fuse issue? And where is the fuse box located?

The boot lock doesn't now work automatically (doesn't fully lock) , and I have to operate the door locks manually ( press down)

Any ideas?
TIA
Tim
 
Hi, I've had my 350 for a month or so and today found after driving her for a few miles and parking up, that I couldn't use the key fob to operate the door or boot locks. All other elements (alarm, courtesy lights etc) work off the fob, but no mechanical locks operate. The car starts and runs fine too.....

I was able to access the car and boot from the metal key, so got around the issue, but looking for some help.

Is this a fuse issue? And where is the fuse box located?

The boot lock doesn't now work automatically (doesn't fully lock) , and I have to operate the door locks manually ( press down)

Any ideas?


Hello RatlerRatler,

It sounds very much like the fuse has blown to the PSE (pneumatic system equipment) pump. Have a look under the driver’s side rear seat/stowage compartment; you will find the fusebox located in here. Its fuse number 71 - 20amp yellow fuse - see attached photo, I’ve already outlined the fuse in yellow.

If this fuse has blown, then its blown for a very good reason, these pumps generally suffer from water ingress and the systems printed circuit board usually gets water contaminated.

Regards,

Dash1

 

Attachments

  • R230 Rear Fusebox.jpg
    R230 Rear Fusebox.jpg
    46 KB · Views: 36
Many thanks Dash1
Where is the pump located?

Would the lock system be pneumatic.?

If this has been affected by water, I can check this area first.

Thanks
Tim
 
Many thanks Dash1
Where is the pump located?

Would the lock system be pneumatic.?

If this has been affected by water, I can check this area first.

Thanks
Tim

Hi RattlerRattler,

The PSE pump unit is located in the boot on the left hand side – see attached photo, again I have marled it in yellow. If you are a “hands-on” type of chap, then you should be able to remove it and check the inside for any contamination. Check the fuse first before you get involved with the pump, if the fuse has blown, then investigate the pump.

Regards,

Dash1

 

Attachments

  • PSE Control Pump - Module.jpg
    PSE Control Pump - Module.jpg
    44.6 KB · Views: 42
Yes, sorry, the locks are pneumatic.

Regards,

Dash1
 
Well, taking Dash1's excellent advice (many thanks Dash1) I checked the fuse and indeed it was blown - working on the approach that this was the result not the cause of the issue, I ventured into the boot to investigate the PSE unit before I replaced the fuse.

There was little sign of any damp in the boot as I removed the spare wheel cover, took out all of the various foam elements and unbolted the power roof motor. This process was relatively easy and if you're careful can be easily performed even by a novice like me.

Once I got to the bootom of the PSE motor, I found that the foam element that the PSE sits in had a very slight damp area underneath, but insufficient in my view to have caused any motor failure (i doubt it would have even been noticeable on the top of the foam). But I removed all the foam elements anyway and used a hairdryer to ensure all was dry.

I then put a plastic grid under the PSE foam element (to keep the foam from being directly in contact with the boot floor), assuming that if this area did get damp in the future, this would allow the foam to only absorb water if the puddle was 5mm deep or so, so minimising any impacts. I then refitted the PSE and roof motor etc....

I then replaced the 20amp fuse with a 25amp fuse as suggested on here and all whirred into life and normality was restored.

I was due to get the SL checked over at a garage tomorrow, so this is no longer required, so many thanks to Dash who has saved me some money!!! - although as I'm not sure I found a fault, this may only be a temporary fix???

Was the damp the cause of the fault - I'm not sure, but I know I'm more familiar now with some the SL's workings, and know where the fuse box is ;)

I've also looked at the other threads on leaking roofs/boots and have cleaned up the rubbers all around the roof.... it was too wet today to really check the roof for leaks, but I want to really clean these areas up and get it sealed up....

I'll keep a watching brief and a fuse handy......

What a great site this is ..... Tim
 
Hello folks, I am having the PSE problems now with my 2005 SL350. Having taken the above advice I removed the PSE unit and separated the black box to get into it. There has certainly been some serous water damage and corrosion to the connectors. All dry now and cleaned up. Though on very close examination is see that pin 2 on the main connector block does not connect through to the PCB. I am concerned that it has corroded away. Does anyone have a circuit diagram of the PCB or the 10 pin connector pin layout and designation. Just maybe it is not used, although I feel that is a forlorn hope. Thanks Ian S
 
There is a guy on ebay that will re-furb it for you.
 

Users who are viewing this thread

Back
Top Bottom