Page 512 of 1500

FRONT SEAT ASSEMBLY
INTERIOR52A-23
INSPECTIONM1522005500113
POWER SEAT CONTINUITY AND DIAGNOSIS
CHECK
SPECIAL TOOL:
MB991219: Inspection Test Harness
CIRCUIT DIAGRAMS:
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80
NOTE: Check connectors and terminals for damage or
loose connections at the seat harness and all supply
circuits connections to seat. Repair or replace wiring
harness if damaged.
NON-MEMORY SEAT DIAGNOSIS
POWER SEAT SUPPLY AND GROUND CONNECTOR (D-40)
NOTE: The special tool (Inspection test harness) MB991219
for connector pin contact pressure should be used. The test
probe should never be forcibly inserted, as it may cause a
defective contact.
4-WAY TRACK (NON MEMORY)
NOTE: The special tool (Inspection test harness) MB991219
for connector pin contact pressure should be used. The test
probe should never be forcibly inserted, as it may cause a
defective contact. SUPPLY TEST
CONNECTION
(D-40) SPECIFIED CONDITION
BATTERY
SUPPLY112V
GROUND 2 Less than 2 ohms or 0V
SWITCH POSITION TEST CONNECTION SPECIFIED CONDITION
SWITCH MOTOR
REAR LIFT MOTOR UP 1 1 Less than 2 ohms
DOWN 4 5 Less than 2 ohms
FRONT LIFT MOTOR UP 2 1 Less than 2 ohms
DOWN 3 5 Less than 2 ohms
Page 514 of 1500

FRONT SEAT ASSEMBLY
INTERIOR52A-25
MEMORY SEAT DIAGNOSIS
POWER SEAT SUPPLY AND GROUND CONNECTOR (D-40)
SPECIAL TOOL:
MB991219: Inspection Test Harness
CIRCUIT DIAGRAMS:
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80
NOTE: Check connectors and terminals for damage or
loose connections at the seat harness and all supply
circuits connections to seat. Repair or replace wiring
harness if damaged.
NOTE: The special tool (Inspection test harness) MB991219
for connector pin contact pressure should be used. The test
probe should never be forcibly inserted, as it may cause a
defective contact.
10-WAY TRACK (MEMORY)- SOURCE TO (MSC) POWER
CONNECTOR (D-38)
NOTE: The special tool (Inspection test harness) MB991219
for connector pin contact pressure should be used. The test
probe should never be forcibly inserted, as it may cause a
defective contact. SUPPLY TEST
CONNECTION
(D-40) SPECIFIED CONDITION
BATTERY
SUPPLY112V
GROUND 2 Less than 2 ohms or 0V
CIRCUIT
DESCRIPTION TEST CONNECTION
(MSC)
POWER
(D-38) SOURCE INTERMEDIATE
CONNECTOR
GROUND 1 GROUND 15 -
"NEUTRAL" 2 A/T-ECU (B-19) 31 (B-25) pin 9
Bus LT 3 - -
IGNITION- LED ON 4 (IGN 2) J/B fuse 9 (C-28) pin 35
DOOR SW.- LED ON 5 RH Door sw. (D-34) 2 -
VEHICLE SPEED 6 A/T-ECU (B-19) 24 (C-25) pin 8
"PARK" 7 A/T-ECU (B-19) 30 (C-25) pin 10
N.C - - -
Page 515 of 1500

FRONT SEAT ASSEMBLY
INTERIOR52A-26
10-WAY TRACK (MEMORY)-switch to module- 20 pin
CIRCUIT DIAGRAMS:
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80
NOTE: Check connectors and terminals for damage or
loose connections at the seat harness and all supply
circuits connections to seat. Repair or replace wiring
harness if damaged.
NOTE: The special tool (Inspection test harness) MB991219
for connector pin contact pressure should be used. The test
probe should never be forcibly inserted, as it may cause a
defective contact.
10-WAY TRACK (MEMORY) 12pin connector (A) at module
to motor circuits
NOTE: The special tool (Inspection test harness) MB991219
for connector pin contact pressure should be used. The test
probe should never be forcibly inserted, as it may cause a
defective contact. SWITCH POSITION TEST CONNECTION SPECIFIED CONDITION
SWITCH (MSC)
MODULE
20 PIN
REAR LIFT MOTOR UP 7 16 Less than 2 ohms
DOWN 8 13 Less than 2 ohms
FRONT LIFT MOTOR UP 6 5 Less than 2 ohms
DOWN 9 7 Less than 2 ohms
TRACK/ SLIDE MOTOR FORWARD 10 4 Less than 2 ohms
BACK 3 3 Less than 2 ohms
RECLINING MOTOR FORWARD 4 14 Less than 2 ohms
BACK 2 2 Less than 2 ohms
SWITCH POSITION TEST CONNECTION SPECIFIED CONDITION
(MSC)
MODULE
12 PIN(A) MOTOR
REAR LIFT MOTOR UP 2 1 Less than 2 ohms
DOWN 3 5 Less than 2 ohms
FRONT LIFT MOTOR UP 11 5 Less than 2 ohms
DOWN 10 1 Less than 2 ohms
TRACK/ SLIDE MOTOR FORWARD 4 2 Less than 2 ohms
BACK 9 1 Less than 2 ohms
Page 516 of 1500

FRONT SEAT ASSEMBLY
INTERIOR52A-27
10-WAY TRACK (MEMORY) lumbar switch to module
(20-pin)
CIRCUIT DIAGRAMS:
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80
NOTE: Check connectors and terminals for damage or
loose connections at the seat harness and all supply
circuits connections to seat. Repair or replace wiring
harness if damaged.
NOTE: The special tool (Inspection test harness) MB991219
for connector pin contact pressure should be used. The test
probe should never be forcibly inserted, as it may cause a
defective contact.
10-WAY TRACK (MEMORY) lumbar and recline module
connector (12-pin) to motors
NOTE: The special tool (Inspection test harness) MB991219
for connector pin contact pressure should be used. The test
probe should never be forcibly inserted, as it may cause a
defective contact. SWITCH POSITION TEST CONNECTION SPECIFIED CONDITION
SWITCH (MSC)
MODULE
LUMBAR SWITCH SOFTER 2 12 (20pin) Less than 2 ohms
HARDER 4 6 (20pin) Less than 2 ohms
MEMORY 3 6 (16pin) Less than 2 ohms
SWITCH POSITION TEST CONNECTION SPECIFIED CONDITION
(MSC)
MODULE
12 PIN MOTOR
LUMBAR MOTOR SOFTER 7 1 Less than 2 ohms
HARDER 2 2 Less than 2 ohms
RECLINER MOTOR FORWARD 1 1 Less than 2 ohms
BACK 8 5 Less than 2 ohms
Page 518 of 1500
FRONT SEAT ASSEMBLY
INTERIOR52A-29
OPERATION CHECK OF POWER SEAT MOTOR
CIRCUIT DIAGRAMS:
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80
NOTE: Check connectors and terminals for damage or
loose connections at the seat harness and all supply
circuits connections to seat. Repair or replace wiring
harness if damaged.
MOTOR DESCRIPTION TERMINAL MEASUREMENT
TRACK/ SLIDE MOTOR BACKWARD 1 MOTOR ON= 12V
MOTOR OFF = GROUND.
FORWARD 2 MOTOR ON= 12V
MOTOR OFF = GROUND.
FRONT LIFT MOTOR UP 1- non memory
5- memoryMOTOR ON= 12V
MOTOR OFF = GROUND.
DOWN 5- non memory
1- memoryMOTOR ON= 12V
MOTOR OFF = GROUND.
REAR LIFT MOTOR UP 1 MOTOR ON= 12V
MOTOR OFF = GROUND.
DOWN 5 MOTOR ON= 12V
MOTOR OFF = GROUND.
RECLINER MOTOR FORWARD 1 MOTOR ON= 12V
MOTOR OFF = GROUND.
BACKWARD 5 MOTOR ON= 12V
MOTOR OFF = GROUND.
LUMBAR MOTOR SOFTER 1 MOTOR ON= 2.5V - 5V
MOTOR OFF = GROUND.
HARDER 2 MOTOR ON= 2.5V - 5V
MOTOR OFF = GROUND.
Page 519 of 1500
FRONT SEAT ASSEMBLY
INTERIOR52A-30
1.If abnormality was found, check the power seat
adjuster assembly.
CIRCUIT DIAGRAMS:
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80
NOTE: Check connectors and terminals for damage or
loose connections at the seat harness and all supply
circuits connections to seat. Repair or replace wiring
harness if damaged.
Page 521 of 1500

FRONT SEAT ASSEMBLY
INTERIOR52A-32
CIRCUIT DIAGRAMS:
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80
NOTE: Check connectors and terminals for damage or
loose connections at the seat harness and all supply
circuits connections to seat. Repair or replace wiring
harness if damaged.
ERASING DIAGNOSTIC TROUBLE CODES (DTC’s)
The Memory Seat Controller will temporarily store DTC’s when
incorrect operating conditions are detected. The DTC’s are
self-clearing as soon as each fault condition is rectified and
returns to normal operating function. LED FLASH
SEQUENCEFAULT CONDITION
DETECTEDPOSSIBLE CAUSE
2 then 1 No fore lift motor sensor Connection at motor sensor
or open/ short circuit in
wiring harness.
2 then 2 No aft lift motor sensor Connection at motor sensor
or open/ short circuit in
wiring harness.
2 then 3 No track motor sensor Connection at motor sensor
or open/ short circuit in
wiring harness.
2 then 4 No pedal motor sensor Connection at motor sensor
or open/ short circuit in
wiring harness.
2 then 5 No recliner motor sensor Connection at motor sensor
or open/ short circuit in
wiring harness.
2 then 6 No lumbar motor sensor Connection at motor sensor
or open/ short circuit in
wiring harness.
3 then 1 Button stuck MEMORY Button switch cap stuck on
side cover
3 then 2 Manual Button stuck position Button switch cap stuck on
side cover
6 then 3 Power relay welded shut Grime on contact
Page 550 of 1500
80-1
GROUP 80
CONFIGURATION
DIAGRAMS
CONTENTS
OVERALL CONFIGURATION
DIAGRAM. . . . . . . . . . . . . . . . . . . . . .80-2
HOW TO READ CONFIGURATION
DIAGRAMS . . . . . . . . . . . . . . . . . . . .80-3
ENGINE COMPARTMENT. . . . . . . . .80-4ENGINE AND TRANSMISSION . . . . .80-6
DASH PANEL . . . . . . . . . . . . . . . . . . .80-10
FLOOR, SEAT AND ROOF . . . . . . . .80-17
DOOR . . . . . . . . . . . . . . . . . . . . . . . . .80-23
LUGGAGE COMPARTMENT . . . . . . .80-24