Page 1401 of 2395
DIAGNOSTIC PROCEDURE 11=NBEL0214S14(Cancel switch check)
1 CHECK CANCEL SWITCH
1. Disconnect cancel switch connector.
2. Check continuity between cancel switch terminals.
SEL628WA
OK or NG
OK©Check the following.
IGround circuit for cancel switch
IHarness for open or short between seat control unit LH and cancel switch
NG©Replace cancel switch.
AUTOMATIC DRIVE POSITIONER
Trouble Diagnoses (Cont'd)
EL-216
Page 1402 of 2395
DIAGNOSTIC PROCEDURE 12=NBEL0214S15(Key, detention, door switch and vehicle speed sensor check)
1 CHECK KEY SWITCH INPUT SIGNAL
Check voltage between seat control unit LH terminal 2 and ground.
SEL629W
OK or NG
OK©GO TO 2.
NG©Check the following.
I7.5A fuse [No. 24, located in fuse block (J/B)]
IKey switch
IHarness for open or short between key switch and fuse
IHarness for open or short between seat control unit LH and key switch
2 CHECK IGNITION SWITCH INPUT SIGNAL (ON AND START)
Check voltage between seat control unit LH terminals and ground.
SEL630W
OK or NG
OK©GO TO 3.
NG©Check the following.
I7.5A fuse [No. 11, located in fuse block (J/B)]
I7.5A fuse [No. 26, located in fuse block (J/B)]
IHarness for open or short between seat control unit LH and fuse
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AUTOMATIC DRIVE POSITIONER
Trouble Diagnoses (Cont'd)
EL-217
Page 1403 of 2395
3 CHECK PARK POSITION SWITCH INPUT SIGNAL
Check voltage between seat control unit LH terminal 21 and ground.
SEL631W
OK or NG
OK©GO TO 4.
NG©Check the following.
IPark position switch
IPark position switch ground circuit
IHarness for open or short between seat control unit LH and park position switch
4 CHECK DRIVER DOOR SWITCH INPUT SIGNAL
Check voltage between seat control unit LH terminal 9 and ground.
SEL632W
OK or NG
OK©GO TO 5.
NG©Check the following.
IDriver door switch
IDriver door switch ground circuit
IHarness for open or short between seat control unit LH and driver door switch
5 CHECK VEHICLE SPEED SENSOR
Does speedometer operate normally?
YesorNo
OK©GO TO 6.
NG©Check speedometer and vehicle speed sensor circuit. Refer to EL-104.
AUTOMATIC DRIVE POSITIONER
Trouble Diagnoses (Cont'd)
EL-218
Page 1404 of 2395
6 CHECK VEHICLE SPEED SENSOR PULL UP VOLTAGE
1. Turn ignition switch ªONº.
2. Check voltage between seat control unit LH terminal 32 and ground.
SEL633W
OK or NG
OK©Harness for open or short between seat control unit LH and combination meter.
NG©Repair harness.
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AUTOMATIC DRIVE POSITIONER
Trouble Diagnoses (Cont'd)
EL-219
Page 1405 of 2395

DIAGNOSTIC PROCEDURE 13=NBEL0214S16(Seat memory switch check)
1 CHECK SEAT MEMORY SWITCH
1. Disconnect seat memory switch connector.
2. Check continuity between seat memory switch terminals.
SEL634WA
OK or NG
OK©Check the following.
IGround circuit for seat memory switch
IHarness for open or short between seat control unit LH and seat memory switch
NG©Replace seat memory switch.
DIAGNOSTIC PROCEDURE 14NBEL0214S17(Memory indicator check)
1 CHECK INDICATOR LAMP
Check indicator lamp illumination.
OK or NG
OK©GO TO 2.
NG©Replace seat memory switch (indicator lamp).
2 CHECK POWER SUPPLY CIRCUIT FOR INDICATOR LAMP
1. Disconnect seat memory switch connector.
2. Check voltage between seat memory switch terminal and ground.
SEL635WA
OK or NG
OK©Check harness for open or short between seat control unit LH and seat memory switch
NG©Check the following.
I7.5A fuse [No. 24 located in the fuse block (J/B)]
IHarness for open or short between fuse and indicator lamp
AUTOMATIC DRIVE POSITIONER
Trouble Diagnoses (Cont'd)
EL-220
Page 1406 of 2395
Component Parts and Harness Connector
Location
NBEL0094
SEL362X
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AUTOMATIC SPEED CONTROL DEVICE (ASCD)
Component Parts and Harness Connector Location
EL-221
Page 1407 of 2395

System DescriptionNBEL0216Refer to Owner's Manual for ASCD operating instructions.
POWER SUPPLY AND GROUNDNBEL0216S01Power is supplied at all times:
Ithrough 10A fuse [No. 14, located in the fuse block (J/B)]
Ito the stop lamp switch terminal 1, and
Ithrough 7.5A fuse (No. 52, located in fuse and fusible link box)
Ito the horn relay terminals 1 and 3.
When ignition switch is in the ON or START position, power is supplied:
Ithrough 7.5A fuse [No. 11, located in the fuse block (J/B)]
Ito ASCD brake switch terminal 1 and
Ito ASCD control unit terminal 5,
Ithrough 10A fuse [No. 18, located in the fuse block (J/B)]
Ito park/neutral position relay terminal 1,
Ithrough 10A fuse [No. 8, located in the fuse block (J/B)]
Ito combination meter terminal 66, and
When park/neutral position switch is in the P or N position, ground is supplied:
Ito park/neutral position relay terminal 2
Ithrough park/neutral position switch and body grounds B55 and B75.
When ASCD main switch is depressed (ON), ground is supplied:
Ito ASCD control unit terminal 9
Ifrom ASCD steering switch terminal 4
Ito ASCD steering switch terminal 5
Ithrough body grounds M4, M66 and M147
then ASCD control unit holds CRUISE condition and illuminates CRUISE indicator.
Ground is supplied:
Ifrom ASCD control unit terminal 15
Ito combination meter terminal 46.
OPERATIONNBEL0216S02Set OperationNBEL0216S0201To activate the ASCD, all following conditions must exist.
IGround supply to ASCD control unit terminal 9 (Main switch is in ON position.)
IPower supply to ASCD control unit terminal 8 (Brake pedal is released and A/T selector lever is in other
than P and N position.)
IVehicle speed is between 40 km/h (25 MPH) and 144 km/h (89 MPH). (Signal from combination meter)
When the SET/COAST switch is depressed, power is supplied:
Ifrom ASCD steering switch terminal 2
Ito ASCD control unit terminal 11.
And then ASCD pump is activated to control throttle wire and ASCD control unit supply ground
Ito combination meter terminals 51 to illuminate SET indicator.
A/T Overdrive Control during Cruise Control DrivingNBEL0216S0202When the vehicle speed is approximately 3 km/h (2 MPH) below set speed, a signal is sent
Ifrom ASCD control unit terminal 10
Ito TCM (transmission control module) terminal 24.
When this occurs, the TCM (transmission control module) cancels overdrive.
After vehicle speed is approximately 1 km/h (1 MPH) below set speed, overdrive is reactivated.
ASCD Shifting ControlNBEL0216S0203During ASCD cruise, ASCD control unit controls A/T shifting to avoid uncomfortable shifting.
This is used to control the signals below.
IThrottle position sensor from ECM
AUTOMATIC SPEED CONTROL DEVICE (ASCD)
System Description
EL-222
Page 1408 of 2395

IA/T shift solenoid valve A
Coast OperationNBEL0216S0204When the SET/COAST switch is depressed during cruise control driving, ASCD actuator returns the throttle
cable to decrease vehicle set speed until the switch is released. And then ASCD will keep the new set speed.
Accel OperationNBEL0216S0205When the RESUME/ACCEL switch is depressed, power is supplied
Ifrom ASCD steering switch terminal 3
Ito ASCD control unit terminal 24.
If the RESUME/ACCEL switch is depressed during cruise control driving, ASCD actuator pulls the throttle cable
to increase the vehicle speed until the switch is released or vehicle speed is reached to maximum controlled
speed by the system. And then ASCD will keep the new set speed.
Cancel OperationNBEL0216S0206When any of following condition exists, cruise operation will be canceled.
ICANCEL switch is depressed. (Power supply to ASCD control unit terminals 11 and 24)
IBrake pedal is depressed. (Power supply to ASCD control unit terminal 23 from stop lamp switch)
IBrake pedal is depressed or A/T selector lever is shifted to P or N position. (Power supply to ASCD con-
trol unit terminal 8 is interrupted.)
If MAIN switch is turned to OFF during ASCD is activated, all of ASCD operation will be canceled and vehicle
speed memory will be erased.
Resume OperationNBEL0216S0207When the RESUME/ACCEL switch is depressed after cancel operation other than depressing MAIN switch is
performed, vehicle speed will return to last set speed. To resume vehicle set speed, vehicle condition must
meet following conditions.
IBrake pedal is released.
IA/T selector lever is in other than P and N position.
IVehicle speed is between 40 km/h (25 MPH) and 144 km/h (89 MPH).
ASCD PUMP OPERATIONNBEL0216S03The ASCD pump consists of a vacuum motor, an air valve and a release valve. When the ASCD activates,
power is supplied
Ifrom terminal 12 of ASCD control unit
Ito ASCD pump terminal 1.
Ground is supplied to vacuum motor, air valve and release valve from ASCD control unit depending on the
operated condition as shown in the below table.
The pump is connected to ASCD actuator by vacuum hose. When the ASCD pump is activated, the ASCD
pump vacuum the diaphragm of ASCD actuator to control throttle cable.
Air valve (*1) Release valve (*1) Vacuum motorActuator inner pres-
sure
ASCD not operating Open Open Stopped Atmosphere
ASCD operatingReleasing throttle
cableOpen Closed Stopped Vacuum
Holding throttle
positionClosed Closed Stopped Vacuum (*2)
Pulling throttle cable Closed Closed Operated Vacuum
*1: When power and ground is supplied, valve is closed.
*2: Set position held.
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AUTOMATIC SPEED CONTROL DEVICE (ASCD)
System Description (Cont'd)
EL-223