Have been wanting to install seat heating option in my 400e. From what I've been able to learn on this board, switching seats with ones that already have such an option should be easier than rebuilding the seats themselves. Have a potentially great deal on a set of 1993 400e seats that may have seat heaters. They have one set of 8 cables wrapped together, one set of 6 cables wrapped together, then two sets of 2 smaller wires each. From what I can see under my current non-heated front seats, one of these sets of wrapped cables may indeed be for seat heater option. Anyone have a wiring diagram or other source for such information to help me ascertain the answer? Secondly, would the wiring harness be present in the console such that I could add appropriate switches and cabling to complete such a seat switch? A third unrelated question, in what year did the w124 (400e model) switch from the standard seat arm rest to the flip up compartment model? Was it 1993? Thanks for any assistance!

Cfmact1,

Each seat should have one plug, the femal clipped onto the outer real (front-inside). There are 4 contacts : 2 for the seat and 2 for the back.
Following the wiring diagram all the wires are 0.75 square milimeter in section. The colors of the wires at the femal plugs are :
Left seat : 1 brown/white mass via steering unit N 25/5 (pin 1)
1 black/blue from pin 2 to pin 3 in plug
Left back : 1 black/blue to pin 3 : arrival of current from N 25/5
1 brown (mass) from pin 4 going to Z5 soldered in cable harness;
Right seat : 1 brown/yellow mass from N 25/5 (pin 1)
1 black/violet from pin 2 to 3 in plug
Right back : 1 black/ violet on pin 3 : power from N 25/5
2 brown wires on pin 4 : one to Z5, one to the switch of the right
seatheating (pin 6 in this plug).

I hope that with the colors you will be able to sort it out. Maybe there is a prewiring for the orthopedical seat/electric adjustment to. I don't have diagrams of these!
Good luck,

Danny

Presently getting close to testing a retrofit in a 190E 16 valve. Time involved is about 30 hours, cost at about $225. It is a hybred system with elements from a Volvo 240DL, thermostats from a Volvo 850, switches from a 560SEL and a relay set from J B Saunders. It is a single function system which will turn on or off the back and bottom at one time. The 560 switch is a control swith only operating a ground and is a daul function when used with a MB controler ( I do not know the P/N or cost ). I have 'breadboard' engineered a relay pak which consists of one double pole power relay and one control relay per seat.

The tear down of the seats is probably half of the job. It is a slow go to get started. Ratcheting cargo straps, picks, hooks and screwdrivers are required for this. I also drilled holes in the seat rails for a 1/4 inch extension in order to remove the aft seat bolts without some special removal tool.

The MB 560SEL switches and pins were new and purchased through Phil. I will get the P/N's to you later.

BTW, My lovely wife considers seat heaters to be a safety feature, claiming that it is impossible to hang on to the steering wheel if she is shivering!

Here is a possible new element source from IPDUSA. http://www.ipdusa.com/SearchResults.aspx
I have searched Ebay for a considerable time for any used MB seat heater parts and have found nothing. If you desire to put in genuine MB, give Phil a call for parts. My only design criteria was to have period ( '87 ) type switches that will be installed in the shifter switch panel.

__________________
'87 190E 2.3-16
Heated Seats, Graphite Dash,
Delsing shift bushings

More info;

P/N 1268206810 Switch, 2 req'd
P/N 0015454426 Pin, 12 req'd
P/N 0008210738 Connector, 2 req'd, note the back lock to this connector was not available so the pins will need to be potted with silicone or an epoxy.

Power was obtained from fuse #10, this was labelled on the fuse cover for seat heat, the fuse was upgraded from a 8A to a 16A per the fuse cover placard. Fuse #10 feeds through the fuse block to connector #L in the cabin interior. Connector #L is a 2 pin on the forward end of the block, verify with a DVM.

More later....

__________________
'87 190E 2.3-16
Heated Seats, Graphite Dash,
Delsing shift bushings