Test step
|
Test scope
|
Test connection
|
Test condition
|
Nominal value
|
Possible cause/Remedy
|
| 1.0 |
Rear HS control
module (N25/6)
Voltage supply
Circuit 30
Circuit 15
Circuit 15C |
9 
9
9
|
|
|
Ignition: OFF
Ignition: ON
Ignition/starter switch in position "0"
Ignition key inserted
Ignition key removed
|
11 - 14 V
11 - 14 V
11 - 14 V
0 - 1 V |
Wiring,
Combination relay module (N10/2). |
| 2.0 |
Rear HS control
module (N25/6)
Voltage supply
Circuit 58d |
9
|
N25/6
 |
 18
|
Parking lamps turned off
Parking lamps turned on |
0 - 1 V
11 - 14 V
|
Wiring. |
| 3.0 |
Left rear seat heater
switch (S51/3)
Voltage supply |
9
|
N25/6
|
13
|
Ignition: ON
S51/3 Stage II held in depressed position
S51/3 Stage I held in depressed position |
6 - 8 V
0 - 1 V
2 - 4 V |
3.1,
Rear HS control module (N25/6). |
| 3.1 |
Left rear seat heater
switch (S51/3)
Resistance |
9
|
N25/6
 |
13
|
Ignition: OFF
Disconnect test cable from N25/6.
S51/3 Stage II held in depressed position
S51/3 Stage I held in depressed position
|
>20 k
0 - 2
Approx. 165 |
Wiring,
Left rear seat heater switch (S51/3). |
| 4.0 |
Left rear seat cushion heater
element (R13/5) and left rear backrest heater
element (R13/6)
Voltage supply |
9
19
9
9
|
|
|
Ignition: ON
Left rear seat heater switch (S51/3) stage II switched on.
S51/3 stage I switched on |
0 - 1 V
9 - 14 V
9 - 14 V
5 - 7 V
9 - 14 V
|
4.1
Rear HS control module (N25/6). |
| 4.1 |
Resistance |
19
8
|
|
8
9
|
Ignition: OFF
Disconnect test cable from N25/6. |
2.0 - 3.0
2.0 - 3.0 |
Wiring,
Left rear seat cushion heater element (R13/5),
Left rear backrest heater
element (R13/6).
|
| 5.0 |
Right rear seat cushion heater
element (R13/7) and right rear backrest heater
element (R13/8)
Voltage supply |
9
4
9
9
|
|
|
Ignition: ON
Right rear seat heater switch (S51/4) stage II switched on.
S51/4 stage I switched on |
0 - 1 V
9 - 14 V
9 - 14 V
5 - 7 V
9 - 14 V
|
5.1
Rear HS control module (N25/6). |
| 5.1 |
Resistance |
2
9
|
|
4
2
|
Ignition: OFF
Disconnect test cable from N25/6. |
2.0 - 3.0
2.0 - 3.0 |
Wiring,
Right rear seat cushion heater element (R13/7),
Right rear backrest heater
element (R13/8).
|
| 6.0 |
Left rear seat heater switch (S51/3),
illumination
Voltage supply |
6
|
S51/3
|
5
|
Disconnect plug on S51/3
Turn on parking lamps |
11 - 14 V |
Wiring, |
| 7.0 |
Left rear seat heater
switch (S51/3), indicator lamps
Voltage supply |
9
9
|
|
12
20
|
Ignition: ON
S51/3 Stage I turned on
S51/3 Stage II turned on
S51/3 Stage I turned on
S51/3 Stage II turned on |
0 - 1 V
8 - 13 V
8 - 13 V
0 - 1 V
8 - 13 V
|
Wiring,
Left rear seat heater switch (S51/3),
Rear HS control module (N25/6). |
| 8.0 |
Left rear seat heater switch (S51/3),
dimming
Voltage supply |
9
9
|
|
12
20
|
Ignition: ON
S51/3 Stage I turned on
Parking lamps turned on
Parking lamps turned off
S51/3 Stage II turned on
Parking lamps turned on |
0 - 1 V
8 - 13 V
2.0 - 2.8 V
8 - 13 V
2.0 - 2.8 V
|
Wiring,
Left front seat heater switch (S51/3)
Rear HS control module (N25/6). |
| 9.0 |
Right rear seat heater
switch (S51/4)
Voltage supply |
9
|
N25/6
|
11
|
Ignition: ON
S51/4 Stage II held in depressed position
S51/4 Stage I held in depressed position
|
6 - 8 V
0 - 1 V
2 - 4 V |
9.1,
Rear HS control module (N25/6). |
| 9.1 |
Right rear seat heater
switch (S51/4)
Resistance |
9
|
N25/6
|
11
|
Ignition: OFF
Disconnect test cable from N25/6.
S51/4 Stage II held in depressed position
S51/4 Stage I held in depressed position
|
>20 k
0 - 2
Approx. 165 |
Wiring,
Right rear seat heater switch (S51/4). |
| 10.0 |
Right rear seat heater switch
(S51/4), illumination
Voltage supply |
6
|
S51/4
|
5
|
Disconnect plug on S51/4
Turn on parking lamps |
11 - 14 V |
Wiring. |
11.0
Only 8 and
12 cylinder engines |
Increased CTP (idle) RPM with
seat heating in stage II. |
|
V2
|
2
|
Unplug connector on engine speed
increase diode
matrix (V2).
Seat heater stage II
switched on |
11 - 14 V
|
Wiring,
Rear HS control module (N25/6),
3.0 or 9.0.
Values O.K.:
See DM, Engines, Volume 3, section 6.2 or 6.3 EA, Engine Speed Increase
Diode Matrix Test.
|
| 12.0 |
Right rear seat heater switch
(S51/4), indicator lamps
Voltage supply |
9
9
|
|
5
10
|
Ignition: ON
S51/4 Stage I turned on
S51/4 Stage II turned on
S51/4 Stage I turned on
S51/4 Stage II turned on |
0 - 1 V
8 - 13 V
8 - 13 V
0 - 1 V
8 - 13 V
|
Wiring,
Right rear seat heater
switch (S51/4),
Rear HS control module (N25/6). |
| 13.0 |
Right rear seat heater switch
(S51/4), dimming
Voltage supply |
9
9
|
|
5
10
|
Ignition: ON
S51/4 Stage I turned on
Parking lamps turned on
Parking lamps turned off
S51/4 Stage II turned on
Parking lamps turned on |
0 - 1 V
8 - 13 V
2.0 - 2.8 V
8 - 13 V
2.0 - 2.8 V
|
Wiring,
Left front seat heater switch (S51/4)
Rear HS control module (N25/6). |
Printable
version
