I have just fixed a problem with the seat on my CL55 and this may help others because the fault is surely going to occur elsewhere due to some dumb cable routing at the factory. I noticed that others had posted the problem here in the past - but had recieved no replies.
My passenger seat stopped moving backwards and forwards when tipping the seat forwards and the info screen was permanantly filled with the big red error code 'SEAT BACK NOT LOCKED' - very annoying!
The cause was a broken wire under the seat because it was poorly routed and the movement of the seat eventually rubbed through and damaged the loom.
The seat back has a switch each side and they are easily accessed for examination by lifting up the sides of the cloth apron that hangs down the very back of the seat. the apron is restrained by elastic webbing and the corners will pull out from being tucked under the plastic side pivot covers.
The outside switch raises and lowers the seat base and is operated first when the seat is tipped forwards. The switch nearest to the tunnel is operated second (the seat will not move at all if they switch in the wrong order) and this slides the seat forwards and backwards on its runners.
The switch nearest the tunnel, which is slightly more difficult to access, but can be seen clearly with a torch, has two short wires leading to the main seat loom and the wires easily snag and rub on the actual switch. Combined with the flexing action involved in tipping the seat they are all destined to fatigue and wearing through like mine.
The fix is a pain - and quite fiddly - but I bet the MB dealer will want to charge for an entire seat loom.
Removal of the seat is required and this is easy...but the seat is ridiculously heavy and is easier with two people (absurd!). Motor the seat fully forwards to undo the two rear bolts (a normal bi hex socket will undo the special bolts) then motor the seat fully back to undo the front pair. Wiggle the seat back an inch to unhook it and then tip it back onto the rear seat so that you can disconnect the wiring loom and the vacuum pipe from underneath the front. (they are tricky but some gentle patient fiddling will release the wiring and a good tug will release the vac pipe...especially if you ease the spring fingers out a little with a screwdriver.) Then give yourself a hernia by lifting the whole seat out.
With the seat upside down you may be able to see the broken wires on the inside switch (once you have got over the shock of seeing the mass of nonsense underneath that looks like half the workings of the space shuttle) and to make the wiring easier to manipulate the switch can be removed by undoing the torx bolt on the underside of it.
Basically you then need to make good your wiring and replace everything in reverse order.
(I am not an expert - but 'just in case' I avoided switching the ignition on when the seat was out to avoid the car registering a seat belt failure code seeing as I had just pulled the seat belt wiring plug)
I soldered a new section of wiring between the switch and the loom and re insulated it with heat shrink before carefully routing the new switch wiring link out of harms way with cable ties. The original wire section was only about 2" long but I used 6" so I could route it a bit better than the factory worker did.
I hope this helps solve some frustration and may save somebody main dealer repair bills....
....Now then.....who knows why one of my my xenon lights is often slow to dip and sometimes need a bang on the actual light unit to make it dip??
My passenger seat stopped moving backwards and forwards when tipping the seat forwards and the info screen was permanantly filled with the big red error code 'SEAT BACK NOT LOCKED' - very annoying!
The cause was a broken wire under the seat because it was poorly routed and the movement of the seat eventually rubbed through and damaged the loom.
The seat back has a switch each side and they are easily accessed for examination by lifting up the sides of the cloth apron that hangs down the very back of the seat. the apron is restrained by elastic webbing and the corners will pull out from being tucked under the plastic side pivot covers.
The outside switch raises and lowers the seat base and is operated first when the seat is tipped forwards. The switch nearest to the tunnel is operated second (the seat will not move at all if they switch in the wrong order) and this slides the seat forwards and backwards on its runners.
The switch nearest the tunnel, which is slightly more difficult to access, but can be seen clearly with a torch, has two short wires leading to the main seat loom and the wires easily snag and rub on the actual switch. Combined with the flexing action involved in tipping the seat they are all destined to fatigue and wearing through like mine.
The fix is a pain - and quite fiddly - but I bet the MB dealer will want to charge for an entire seat loom.
Removal of the seat is required and this is easy...but the seat is ridiculously heavy and is easier with two people (absurd!). Motor the seat fully forwards to undo the two rear bolts (a normal bi hex socket will undo the special bolts) then motor the seat fully back to undo the front pair. Wiggle the seat back an inch to unhook it and then tip it back onto the rear seat so that you can disconnect the wiring loom and the vacuum pipe from underneath the front. (they are tricky but some gentle patient fiddling will release the wiring and a good tug will release the vac pipe...especially if you ease the spring fingers out a little with a screwdriver.) Then give yourself a hernia by lifting the whole seat out.
With the seat upside down you may be able to see the broken wires on the inside switch (once you have got over the shock of seeing the mass of nonsense underneath that looks like half the workings of the space shuttle) and to make the wiring easier to manipulate the switch can be removed by undoing the torx bolt on the underside of it.
Basically you then need to make good your wiring and replace everything in reverse order.
(I am not an expert - but 'just in case' I avoided switching the ignition on when the seat was out to avoid the car registering a seat belt failure code seeing as I had just pulled the seat belt wiring plug)
I soldered a new section of wiring between the switch and the loom and re insulated it with heat shrink before carefully routing the new switch wiring link out of harms way with cable ties. The original wire section was only about 2" long but I used 6" so I could route it a bit better than the factory worker did.
I hope this helps solve some frustration and may save somebody main dealer repair bills....
....Now then.....who knows why one of my my xenon lights is often slow to dip and sometimes need a bang on the actual light unit to make it dip??
