1990 560sec seat belt extender problem - PeachParts Mercedes-Benz Forum

BigRed0803 · #1 01-28-2009, 11:16 PM

Another question about the 1990 560SEC. The seat belt extender on the drivers side is now stuck in the extended position. The passenger side works like it should but the drivers side will not retract back in, it stays fully extended all the time. What controls this part, or what do you think has happened to the unit? Thanks

jhodg5ck · #2 01-30-2009, 02:13 AM

Did you check the fuse..? Have you swapped your fuses for copper bits?
More often then not the plastic gear fails.. But it's an older electric motor @ this point so anything is possible!

Jonathan

cdplayer · #3 01-30-2009, 03:03 AM

Ok. You checked the fuses. You checked the pin switches in the door for power. All appears ok. Next you have to remove the rear side panel to get a look at the arm from inside.

The first pic is the extender unit minus the seat belt loop(on left).
Second pic shows the likely break point which is the gear on the right. It's plastic. Do you hear the extender motor running continuously? Try this test. Car off. Ignition key on. Open and shut door. Motor should cycle if the break point gears are broken and not jammed.
The blue wire is attached to the pressure switch. If this gear is not broken is could be jammed with debris. The pressure switch is attached by two screws. Some times these screws loosen up and these small switches can not function.
The third pic shows the componants removed from the support bar. Following the long black cord around almost to the end you see four small chrome like screws. These screws secure two position sensors. These too may loosen out of alignment and the unit ceases to function.
Worst case scenario the unit's brain has failed. That's the black box to the right of the first picture.

BigRed0803 · #4 02-04-2009, 12:11 AM

Thanks alot for the tips, I will give this a try and see what has happened and let you know.