ML350 (W166) Driver seat belt doesn't extend on hot days
 

Hi all, I have noticed a strange problem in my 2014 ML350 Bluetec (w166). On hot days (86F/30C+), if my car is left out in the sun the driver's side seat belt doesn't extend.
For eg. I return to the parked car after its been a few hours in the sun, I get in the car and try and buckle myself in and the seat belt only extends a couple of inches :-(
I have tried pulling the belt extremely slow but it doesn't help. I have to pull a couple of inches, then loosen the pull, then hold it there then pull again *sigh*...this process takes 15-20 mins

Has anyone else had this problem? My car is not in warranty and I have booked it in for dealer to look at.
However, the reason I am posting here is to see if anyone else experienced this and if this is likely a manufacturing fault. My car has done (62000 kms / 38500 miles).

Thanks in advance

It sounds like maybe your belt has folded over in the mechanism, and possibly the surrounding plastic(when heated) is working against you. When cold , pull the belt out in its entirety, and see if it's not folded over. Of course, removing the plastic interior surrounding the belt will verify that it's not folded up right at the beginning. just a thought!

Thanks for the suggestion Koenig1...will give it a try