SL55 keeps blowing fuse for central locking and boot release

[Oli]

The other day I couldn't get the boot open on my car so googled it and found someone else with the same problem, they said that it was a blown fuse so replaced the fuse in question behind the drivers side seat, it has done it again a couple of times since, I've noticed usually when you shut the boot without using the soft close.
Someone else said it can be cause by wetness in the boot causing problems with a sensor?, but the boot all feels dry, around the roof motor and foam etc feels dry too.
Has anyone else had this or has any ideas what could be causing it?.

 

[ACID]

The other day I couldn't get the boot open on my car so googled it and found someone else with the same problem, they said that it was a blown fuse so replaced the fuse in question behind the drivers side seat, it has done it again a couple of times since, I've noticed usually when you shut the boot without using the soft close.
Someone else said it can be cause by wetness in the boot causing problems with a sensor?, but the boot all feels dry, around the roof motor and foam etc feels dry too.
Has anyone else had this or has any ideas what could be causing it?.

Hi,

Usually the boot seal leaks water into the Central locking pump causing the motor inside to seize up and blow the fuse, it is located beneath the roof motor, that is the first thing I would check

 

[Oli]

Thanks, I will check it out, do you know what they cost to replace roughly?.

 

[ACID]

Thanks, I will check it out, do you know what they cost to replace roughly?.

Second hand They would be around £300ish however they are like rocking horse poo to find! New if i recall are around £650 +vat but they may have reduced as it was a short while back,

 

[Oli]

Damn, I've just checked it and the bottom foam was wet, the boot seals have been done though so perhaps this was from before they were done and it has taken until now to play up, not the best thing to find a little after a week of ownership but it could be worse.
Is there any way to waterproof the old unit a little for now until I get a replacement?, the rest of the boot is dry.

 

[Terry_]

Once it blows once it will usually go again. The damage would have been done already. The seal at the bottom of the rear window is the common culprit and can be changed pretty easily.
I would suggest you replace the pump sooner rather than later, as eventually you may not be able to get into the trunk to change it.
This then causes another issue

 

[Oli]

It looks pretty straight forward to DIY the pump, I've just removed the bottom foam section to dry it out for now and will most likely get a new pump and replace at the weekend.

It has had some seals replaced looking at the invoices for it but would rather get it checked out to make sure there is no water ingress after spending £700 ish on a pump.

 

[Terry_]

Just keep the boot separator closed so that the roof can operate !
Yes it is straight forward to replace the pump

 

[Oli]

I've been reading up on this more since earlier, what would the best way to check the seals are all working correctly and no water is getting in would be?, or can anyone reccomend someone that is good with SL seals?, I'm all for getting the PSE pump changed sooner rather than later, I just want to make sure it stays dry and I don't fry another £700 ish part, people have also reccomended wrapping the box in bubble wrap before putting back into the foam to waterproof it somewhat, is this advisable?.

 

[Terry_]

There is nothing wrong with wrapping the pump to protect it! It will be the seal at the bottom of the rear window is at fault. It takes very little time to replace and costs around 150 all in.

 

[richard]

It could also just be that the exit pipes from that bottom seal are blocked .. (they were on mine)

Richard

 

[Darnott]

PSE central locking pump PSE vacuum

Hello,

I have a couple of these units for sale.
All FULLY tested and coded as required.
I can also fit if you can come to lovely warm Aberdeen!

Mercedes Benz SL PSE vacuum pump central locking R230 SL55 SL500 SL350 | eBay


Tel:- 0776 290 2284 or 01224 208650

Regards
David

 

[Blaze1]

Appreciate its been a while since this thread started but I had exactly the same thing happen to my fuse - it happened back in March when we had a cold snap and the the PSE fuse blew. Change that first and then see how you get on.

 

[Blaze1]

Oli (15-04-2013), there is a big DIY section on this on another well known MB forum - don't want to say as I don't want to get myself in trouble!