2001 XK8 Convertible:

Since months I have problem with the driver seatbelt wich occurs at times. It is a loud clicking. Sometimes multiple single clicks sometimes like a machine-gun.
It comes from the seatbelt-unit wich is behind the left rear-cover. When it is clicking I can feel it when i put my hand on it. it does not change when I move the connectors/calbes or belt.

It only occurs when the engine is running and it starts only after I start driving, but it remains when I stop and get into neutral. It goes off when I turn off the engine and leave the key in position.

It gets less when I switch on AC/Heating, Seatheating, Stereo and other electrical components. the more components the less clicking.

The seatbelt works properly and also stopp rolling when I pull the belt quick.

Any suggestion?
Is it a relays that clicks so loud?
Would it help to replace the seatbelt-unit or is it an electrical problem somewhere else?

Daniel

 

It sounds like it could be the seat belt comfort solenoid that's behind the rear quarter panel. It's intended to relieve the tension in the seat belt once its pulled itself in against you (or your passenger) but should just come on and off with the engine. Sounds like a new solenoid if it's not a poor connection, or maybe a whole seatbelt if it's sealed set-up. Or disconnect it if the 'comfort' can be lived without.
You can check the effect on either belt by holding the belt against its normal tension when switching the engine on or off.

 

Thanks for your input.

Seems like this solenoid is part of the seatbelt-unit.

As english is not my mother tongue I did not understand your proposal to check:
"......... either belt by holding the belt against its normal tension when switching the engine on or off."

Thanks - Daniel

 

Sit in the car, seatbelt on and engine running. With finger and thumb, pull the seatbelt slightly against the retraction tension and while holding it, switch off the engine. You should feel a slight additional pull as the comfort solenoid switches off. Both front set belts should be the same.

 

Thanks astromorg, perfect description. Will check in in the next days.

 

I checked all 4 seat belts, and all have no reaction when I switch off the engine and hold the belt between 2 fingers.

But Im pretty sure that this clicking is coming from the comfort solenoid. I saw a explosion-view and there is a bolt with spring witch could occur this clicking.

Am I right that it is the upper connector which leads to the comfort solenoid? What will happen when I take off the connector? Will there be a fault-code?

Thanks

 

Only the two front seat belts have comfort solenoids.
The White/Green wire bringing 12v ignition switched power to the solenoid comes directly from the Driver's Side Fuse Box.
Assuming you have a left hand drive car, the Black/White wire from the driver's solenoid goes under the centre console and via a 20 way Yellow connector and on to the seat belt connector on the driver's seat. It's possible that your problem is there in the Driver's Seat Belt switch itself.
There is no fault code associated with this problem, so it's unlikely that disconnecting at the retractor will cause any problems. I would try it to se if it stops the clicking.
For peace of mind you could also check Fuse 14, 10A in the Drivers Side Fuse Box, but the clicking suggests power is available. That fuse also supplies the passenger side and some other circuits in the car so it's probably OK or you'd have noticed other problems. (Or have you!?)
Hope that's of some help!

 

I checked all wirings and could not find anything. So I disconnected the solenoid.
No failure message and no difference by using the belt. Thats fine for me.

Daniel