Page 476 of 1500
INPUT SIGNAL PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-476
STEP 3. Check the wiring harness between ETACS-ECU
connector C-219 (terminal 20) and battery.
NOTE: Also check junction block connector C-214 for loose,
corroded, or damaged terminals, or terminals pushed back in
the connector. If junction block connector C-214 is damaged,
repair or replace the damaged component(s) as described in
GROUP 00E, Harness Connector Inspection P.00E-2.
Q: Is the wiring harness between ETACS-ECU connector
C-219 (terminal 20) and battery in good condition?
YES : No action is necessary and testing is complete.
NO : The wiring harness may be damaged or the
connector(s) may have loose, corroded or damaged
terminals, or terminals pushed back in the connector.
Repair the wiring harness as necessary. If the
functions or equipment described in "CIRCUIT
OPERATION" work normally, the interior lamp loaded
signal should be normal.
Page 478 of 1500

INPUT SIGNAL PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-478
NOTE: Also check junction block connector C-215 for loose,
corroded, or damaged terminals, or terminals pushed back in
the connector. If junction block connector C-215 is damaged,
repair or replace the damaged component(s) as described in
GROUP 00E, Harness Connector Inspection P.00E-2.
Q: Is the wiring harness between ETACS-ECU connector
C-219 (terminal 8) and the ignition switch (IG1) in good
condition?
YES : No action is necessary and testing is complete.
NO : The wiring harness may be damaged or the
connector(s) may have loose, corroded or damaged
terminals, or terminals pushed back in the connector.
Repair the wiring harness as necessary. If the
functions or equipment described in "CIRCUIT
OPERATION" work normally, the interior lamp loaded
signal should be normal.
STEP 6. Check the ignition switch (ACC) line of the power
supply circuit to the ETACS-ECU. Measure the voltage at
ETACS-ECU connector C-219.
(1) Disconnect ETACS-ECU connector C-219 and measure the
voltage available at the junction block side of the connector.
(2) Turn the ignition switch to the "ACC" position.
(3) Measure the voltage between terminal 18 and ground.
The voltage should measure approximately 12 volts
(battery positive voltage).
Q: Is the measured voltage approximately 12 volts (battery
positive voltage)?
YES : Replace the ETACS-ECU. If the functions or
equipment described in "CIRCUIT OPERATION" work
normally, the interior lamp loaded signal should be
normal.
NO : Go to Step 7.
Page 479 of 1500
INPUT SIGNAL PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-479
STEP 7. Check the wiring harness between ETACS-ECU
connector C-219 (terminal 18) and the ignition switch
(ACC).
NOTE: Also check junction block connector C-215 for loose,
corroded, or damaged terminals, or terminals pushed back in
the connector. If junction block connector C-215 is damaged,
repair or replace the damaged component(s) as described in
Q: Is the wiring harness between ETACS-ECU connector
C-219 (terminal 18) and ignition switch (ACC) in good
condition?
YES : No action is necessary and testing is complete.
NO : The wiring harness may be damaged or the
connector(s) may have loose, corroded or damaged
terminals, or terminals pushed back in the connector.
Repair the wiring harness as necessary. If the
functions or equipment described in "CIRCUIT
OPERATION" work normally, the interior lamp loaded
signal should be normal.
Page 498 of 1500
INSTRUMENT PANEL ASSEMBLY
INTERIOR52A-9
DISASSEMBLY AND ASSEMBLYM1521001900376
DISASSEMBLY STEPS
1. DISTRIBUTION DUCT. REAR
CONSOLE DUCTS REFER TO
GROUP 55 HEATER ,AIR
CONDITIONING AN
VENTILATION P.55-175
2. BACKBONE BRACKET3. AIR BAG MODULE ASSEMBLY
(FRONT PASSENGER’S SIDE)
(REFER TO GROUP 52B, AIR
BAG MODULE(S) AND CLOCK
SPRING P.52B-237.)
4. SIDE DEFROSTER DUCT
5. DEFROSTER NOZZLE
6. COMBINATION METER BRACKET
7. GLOVEBOX STRIKER
8. INSTRUMENT PANELDISASSEMBLY STEPS
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