Some random observations:
I had a problem with the passenger side power seat not working in my
1998 Disco.
Stupidly, I took the switch apart thinking I could fix. If anyone is
contemplating such a move, please don't try it.
If you must clean it, don't disassemble it first. The switch has
mercedes benz markings on it, so it might be available from some model
of merc, but it's prohibitively expensive from LRNA. Once you take it apart,
unless you're Mr. Wizard, you aren't getting it back together.
Of course when such a switch breaks, Murphy's law will ensure that it
leaves the seat in an uncomfortable position. Not wanting to purchase
a switch at this time, I needed to figure out a way to move it, so I
took out the trusty DVM and found out some stuff that might be useful
to someone in the same position I am in.
There are two connectors which connect to the switch. One (the larger
of the two) has six terminals in it (conveniently numbered 1-6) while
the smaller of the two has five actual terminals (inconveniently also
numbered 1-6 due to the presence of a blank in position 4).
Here's the larger Switch:
------------------------------------------
| (4) (2) |
| (6) (5) |
| (3) (1) |
------------------------------------------
Pins 3&4 are negative and positive, respectively when ignition is in
position II. They are a bit larger than the others and conveniently
fit the banana plug end of a standard DVM probe.
5,6 (Front Tilt) and 1,2 (seat forward, aft)are the controls that
actually drive the motor. Applying voltage to the pins will energize
the motor in the selected direction per the following examples:
-5 +6 = Tilt up
+5 -6 = Tilt down
+1 -2 = seat moves aft
-1 +2 = seat moves forward
Here's the smaller Switch:
------------------------------------------
| (3) (5) |
| (1) (2) |
| (4) (6) |
------------------------------------------
Position 4 is a blank
Position 3 is hot when ignition is in position II
I didn't use pin three at all. I used the +/- feeds on the larger
switch to energize the controls on this switch.
+1 -2 = seatback moves down
-1 +2 = seatback moves up
-6 +5 = rear tilt up
+6 -5 = rear tilt down
Once I sorted this information out, I was able to use it to manipulate
the seat into a more comfortable position for my passengers. In
addition, testing the seat functions manually, allowed me to confirm
that indeed the switch was bad and not a motor or some wiring issue.
Good luck with this information and while it's true to the best of my
knowledge, it may be that different model years/trim levels have
different values for the terminals than I describe here so definitely
don't go blindly poking probes and energizing your seats manually just
because I say it worked on my Disco. You could F--- something up
really bad that way.
I had a problem with the passenger side power seat not working in my
1998 Disco.
Stupidly, I took the switch apart thinking I could fix. If anyone is
contemplating such a move, please don't try it.
If you must clean it, don't disassemble it first. The switch has
mercedes benz markings on it, so it might be available from some model
of merc, but it's prohibitively expensive from LRNA. Once you take it apart,
unless you're Mr. Wizard, you aren't getting it back together.
Of course when such a switch breaks, Murphy's law will ensure that it
leaves the seat in an uncomfortable position. Not wanting to purchase
a switch at this time, I needed to figure out a way to move it, so I
took out the trusty DVM and found out some stuff that might be useful
to someone in the same position I am in.
There are two connectors which connect to the switch. One (the larger
of the two) has six terminals in it (conveniently numbered 1-6) while
the smaller of the two has five actual terminals (inconveniently also
numbered 1-6 due to the presence of a blank in position 4).
Here's the larger Switch:
------------------------------------------
| (4) (2) |
| (6) (5) |
| (3) (1) |
------------------------------------------
Pins 3&4 are negative and positive, respectively when ignition is in
position II. They are a bit larger than the others and conveniently
fit the banana plug end of a standard DVM probe.
5,6 (Front Tilt) and 1,2 (seat forward, aft)are the controls that
actually drive the motor. Applying voltage to the pins will energize
the motor in the selected direction per the following examples:
-5 +6 = Tilt up
+5 -6 = Tilt down
+1 -2 = seat moves aft
-1 +2 = seat moves forward
Here's the smaller Switch:
------------------------------------------
| (3) (5) |
| (1) (2) |
| (4) (6) |
------------------------------------------
Position 4 is a blank
Position 3 is hot when ignition is in position II
I didn't use pin three at all. I used the +/- feeds on the larger
switch to energize the controls on this switch.
+1 -2 = seatback moves down
-1 +2 = seatback moves up
-6 +5 = rear tilt up
+6 -5 = rear tilt down
Once I sorted this information out, I was able to use it to manipulate
the seat into a more comfortable position for my passengers. In
addition, testing the seat functions manually, allowed me to confirm
that indeed the switch was bad and not a motor or some wiring issue.
Good luck with this information and while it's true to the best of my
knowledge, it may be that different model years/trim levels have
different values for the terminals than I describe here so definitely
don't go blindly poking probes and energizing your seats manually just
because I say it worked on my Disco. You could F--- something up
really bad that way.
