500SL R107 Strange ticking sound from beneath the glove box

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van883

New Member
Joined
Feb 10, 2009
Messages
28
Car
1989 500SL
I haven't had my R107 SL for long and am getting to know the car gradually. I am puzzled by a ticking noise which sound like a loud indicator relay. It emanates from beneath the glove box. It is NOT the indicators. It seems to come on randomly whilst driving or stationary and sometimes persists for a short while after turning the ignition off. I just induced the noise by opening and shutting the car door. I did not turn the ignition on...and it is hours since I drove it. The sound is definitely within the cabin, beneath the glove box rather than from under the bonnet.

Can anyone help with ideas?

Thanks

Van

Nottingham
UK
 
Is there a courtesy circuit relay fitted to the R107? It certainly sounds like it could be a relay making the noise.
 
van883 said:
What is a courtesy circuit relay? Cheers

A relay that allows power to circuits such as electric windows for a while after the keys are removed from the ignition. Often activated by opening of front doors, if I recall correctly.
 
There are courtesy relays but they are normally all above the fuses drivers side. Merc had a habit of changing things around just to fool us so who knows :dk:
You need to do more investigative work to narrow it down. Take down the dash undertray and maybe the glovebox liner. Pop the light units out and disconnect. The undertray has a few screws only. The liner is held by expansion plugs...prise out the center expander pin then the plug will pop out.
Later cars have the FPR behind the glovebox but I doubt it's that. More likely an alarm control box misbehaving. Does it have an alarm system?
Also the engine ECU is under the carpets passenger side. You need to narrow down the ticking sound to a component.




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Thanks-I will take the undertray off sometime next week. I spoke to Bruce at the SL shop and he said it might be an old "Becker audio unit" making the noise. He said that they had encountered a similar ticking sound on some SLs and that if I find one in there...whatever it is , then disconnect it!

Van
 
It is the right hand relay behind the hatch in the glovebox liner
Here is a picture-anyone any idea what it is please?
the number is 0095451728
thanks

Van
gloveboxrelay_zps4f8cae53.jpg
 
That part number applies to the cover of the plug which connects to the relay. You need to unplug it and release the relay and get its part number.
 
I am realising the part number is just for the cover and that it seemsvto be a plug and socket. But what is it??
 
It's exactly that...a plug. It surely plugs into a component of some sort? If it's just a socket and that goes somewhere else via a cable then that's not the source of your noise. Plugs and sockets are inanimate objects with nothing that could generate noise.

Are you sure the noise isn't coming from the relay attached to the left plug which is the fuel pump relay?




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Jeeez. I know it is a plug. To be specific, can someone help identify what the component that the plug plugs into? What I am looking for is some help with what it is that is making the noise. I could actually feel it clicking and want to know what I am dealing with. I can speculate as well as the next person.
 
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It's exactly that...a plug. It surely plugs into a component of some sort? If it's just a socket and that goes somewhere else via a cable then that's not the source of your noise. Plugs and sockets are inanimate objects with nothing that could generate noise.

Are you sure the noise isn't coming from the relay attached to the left plug which is the fuel pump relay?




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I'll check the fpr then. Thanks
 
What is puzzling me is that on one forum it is "definitely" Not the FPR and on this one it is likely to be that relay in the photo. What is frustrating is that there is no manual to tell me definitively what it is!
 
Jeeez. I know it is a plug. To be specific, can someone help identify what the component that the plug plugs into? What I am looking for is some help with what it is that is making the noise. I could actually feel it clicking and want to know what I am dealing with. I can speculate as well as the next person.

I think that being rude to someone who is trying to help you will not get you very far.....:doh:
 
I apologise. I did not think I was being rude. I should have put a smiley after the "Jeez". I thought I was clarifying what I needed in terms of advice. I had hoped that as the R107 is quite numerous that someone on the forum would be able to identify what can be seen on the photo. I'll take it to a specialist to find out what it is and may post the result.
 

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