Page 519 of 579

DIAGNOSTIC PROCEDURE (TB48 ENGINE EXCEPT
FOR THE MIDDLE EAST)
SYMPTOM: Magnet clutch does not engage when A/C switch
and fan control dial are ON.
CHECK INTAKE SENSOR CIRCUIT.
Refer to self-diagnosis (HA-4027) and
intake sensor circuit (HA-132 in Y61 SER-
VICE MANUAL, publication No. SM7E-
2Y61G1.)
CHECK POWER SUPPLY FOR COM-
PRESSOR.
Disconnect compressor harness connector.
Do approx. 12 volts exist between compres-
sor harness connector terminal No.j
1and
ground?
No
cYe s
Check magnet clutch coil.
NG
Replace magnet clutch.
Refer to HA-178 in Y61
SERVICE MANUAL (publi-
cation No. SM7E-2Y61G1).
Disconnect A/C relay.
Note
CHECK CIRCUIT CONTINUITY
BETWEEN A/C RELAY HARNESS CON-
NECTOR TERMINAL NO.j
3AND COM-
PRESSOR HARNESS CONNECTOR TER-
MINAL NO.j
1.
Continuity should exist.
If OK, check harness for short.
OK
CHECK POWER SUPPLY FOR A/C
RELAY.
Disconnect A/C relay.
Do approx. 12 volts exist between A/C
relay harness connector terminal Nos.j
1,
j5and ground?
Ye s
cNo
Check power supply circuit
and 10A or 20A (No.
)
located in the fuse block
(J/B).
Refer to EL section (ªWiring
Diagramº, ªPOWER SUP-
PLY ROUTINGº).
CHECK A/C RELAY AFTER DISCON-
NECTING IT.
Refer to HA-41 in Y61 SERVICE MANUAL,
publication No. SM1E-Y61EG1.
OK
cNG
Replace A/C relay.
jA(Go to next page.)
Note:
If the result is NG or No after checking circuit continuity, repair harness or
connector.
RHA385I
SHA579F
SHA580FC
SHA581F
.
.
.
.
.
.
.
TROUBLE DIAGNOSESAUTO
Magnet Clutch (Cont'd)
HA-4040
Page 520 of 579

jA
Reconnect A/C relay.
CHECK COIL SIDE CIRCUIT OF A/C
RELAY.
Do approx. 12 volts exist between ECM
harness connector terminal No.j
24and
ground?
Ye s
Ye s
cNo
Disconnect A/C relay.
Disconnect ECM harness
connector.
jB
(Go to next page.)
Note
CHECK CIRCUIT CONTI-
NUITY BETWEEN A/C
RELAY HARNESS CON-
NECTOR TERMINAL NO.
j
2AND ECM HARNESS
CONNECTOR TERMINAL
NO.j
24.
Continuity should exist.
If OK, check harness for
short.
M/T models A/T models
CHECK VOLTAGE FOR ECM.
Do approx. 12 volts exist between ECM
harness connector terminal No.j
86and
ground?
Ye s
cNo
CHECK ECM. Refer to EC
section.
Disconnect ECM harness connector.
Disconnect auto amp. harness connector.
Note
CHECK CIRCUIT CONTINUITY
BETWEEN ECM HARNESS CONNEC-
TOR TERMINAL NO.j
86AND AUTO AMP.
HARNESS CONNECTOR TERMINAL NO.
j
4.
Continuity should exist.
If OK, check harness for short.
OK
CHECK REFRIGERANT PRESSURE
SENSOR.
Refer to EC-498 (publication No.
SM2E-Y61FG1).
OK
cNG
Replace refrigerant pres-
sure sensor.
Replace auto amp.
Note:
If the result is NG or No after checking circuit continuity, repair harness
or connector.
SHA582FB
SHA583F
SHA584FB
RHA386I
.
.
.
.
.
.
.
.
.
TROUBLE DIAGNOSESAUTO
Magnet Clutch (Cont'd)
HA-4041
Page 522 of 579

DIAGNOSTIC PROCEDURE (MODELS WITH TB45
ENGINE)
SYMPTOM: Magnet clutch does not engage when A/C switch
and fan control dial are ON.
CHECK POWER SUPPLY FOR COM-
PRESSOR.
Disconnect compressor harness connector.
Do approx. 12 volts exist between compres-
sor harness connector terminal No.j
1and
ground?
No
cYe s
Check magnet clutch coil.
NG
Replace magnet clutch.
Refer to HA-178 in Y61
SERVICE MANUAL, publi-
cation No. SM7E-2Y61G1.
Disconnect A/C relay.
Note
CHECK CIRCUIT CONTINUITY
BETWEEN A/C RELAY HARNESS CON-
NECTOR TERMINAL NO.j
3AND COM-
PRESSOR HARNESS CONNECTOR TER-
MINAL NO.j
1.
Continuity should exist.
If OK, check harness for short.
OK
CHECK POWER SUPPLY FOR A/C
RELAY.
Disconnect A/C relay.
Do approx. 12 volts exist between A/C
relay harness connector terminal Nos.j
1,
j5and ground?
Ye s
cNo
Check power supply circuit
and 10A or 20A (No.
)
located in the fuse block
(J/B).
Refer to EL section (ªWiring
Diagramº, ªPOWER SUP-
PLY ROUTINGº).
CHECK A/C RELAY AFTER DISCON-
NECTING IT.
Refer to HA-22 in Y61 SERVICE MANUAL,
publication No. SM1E-Y61EG1.
OK
cNG
Replace A/C relay.
jA(Go to next page.)
Note:
If the result is NG or No after checking circuit continuity, repair harness or
connector.
RHA388I
RHA096GG
SHA580FA
SHA581F
.
.
.
.
.
.
TROUBLE DIAGNOSESAUTO
Magnet Clutch (Cont'd)
HA-4043
Page 523 of 579

jA
Reconnect A/C relay.
CHECK COIL SIDE CIRCUIT OF A/C
RELAY.
Do approx. 12 volts exist between ECM
harness connector terminal No.j
9and
ground?
Ye s
cNo
Disconnect A/C relay.
Disconnect ECM harness
connector.
Note
CHECK CIRCUIT CONTI-
NUITY BETWEEN A/C
RELAY HARNESS CON-
NECTOR TERMINAL NO.
j
2AND ECM HARNESS
CONNECTOR TERMINAL
NO.j
9.
Continuity should exist.
If OK, check harness for
short.
CHECK VOLTAGE FOR ECM.
Do approx. 12 volts exist between ECM
harness connector terminal No.j
46and
ground?
Ye s
cNo
CHECK ECM. Refer to EC
section.
Disconnect ECM harness connector.
Disconnect dual-pressure switch harness
connector.
Note
CHECK CIRCUIT CONTINUITY
BETWEEN ECM HARNESS CONNEC-
TOR TERMINAL NO.j
46AND DUAL-
PRESSURE SWITCH HARNESS CON-
NECTOR TERMINAL NO.j
2.
Continuity should exist.
If OK, check harness for short.
OK
CHECK DUAL-PRESSURE SWITCH.
Refer to HA-119 in Y61 SERVICE
MANUAL, publication No. SM7E-2Y61G1.
OK
cNG
Replace dual-pressure
switch.
jB
(Go to next page.)
Note:
If the result is NG or No after checking circuit continuity, repair harness
or connector.
RHA655GC
RHA389I
RHA657GC
RHA390I
.
.
.
.
.
.
.
.
TROUBLE DIAGNOSESAUTO
Magnet Clutch (Cont'd)
HA-4044
Page 525 of 579

DIAGNOSTIC PROCEDURE (MODELS WITH TD
ENGINE)
SYMPTOM: Magnet clutch does not engage when A/C switch
and fan control dial are ON.
CHECK POWER SUPPLY FOR COM-
PRESSOR.
Disconnect compressor harness connec-
tor.
Do approx. 12 volts exist between com-
pressor harness terminal No.j
1and
ground?
No
cYe s
Check magnet clutch coil.
NG
Replace magnet clutch.
Refer to HA-178 in Y61
SERVICE MANUAL, publi-
cation No. SM7E-2Y61G1.
Disconnect A/C cut relay.
Note
CHECK CIRCUIT CONTINUITY
BETWEEN A/C CUT RELAY HARNESS
CONNECTOR TERMINAL NO.j
3AND
COMPRESSOR HARNESS CONNECTOR
TERMINAL NO.j
1.
Continuity should exist.
If OK, check harness for short.
OK
CHECK A/C CUT RELAY.
Refer to HA-4051.
OK
cNG
Replace A/C cut relay.
Note
CHECK CIRCUIT CONTINUITY
BETWEEN A/C RELAY HARNESS CON-
NECTOR TERMINAL NO.j
7AND A/C
CUT RELAY HARNESS CONNECTOR
TERMINAL NO.j
4.
Continuity should exist.
If OK, check harness for short.
OK
j
A
(Go to next page.)
Note:
If the result is NG or No after checking circuit continuity, repair harness
or connector.
RHA392I
SHA579F
SHA580F
RHA393I
.
.
.
.
.
.
TROUBLE DIAGNOSESAUTO
Magnet Clutch (Cont'd)
HA-4046
Page 528 of 579

DIAGNOSTIC PROCEDURE (MODELS WITH ZD
ENGINE)
SYMPTOM: Magnet clutch does not engage when A/C switch
and fan control dial are ON.
CHECK POWER SUPPLY FOR COM-
PRESSOR.
Disconnect compressor harness connector.
Do approx. 12 volts exist between compres-
sor harness connector terminal No.j
1and
ground?
No
cYe s
Check magnet clutch coil.
NG
Replace magnet clutch.
Refer to HA-178 in Y61
SERVICE MANUAL, publi-
cation No. SM7E-2Y61G1.
Disconnect A/C relay.
Note
CHECK CIRCUIT CONTINUITY
BETWEEN A/C RELAY HARNESS CON-
NECTOR TERMINAL NO.j
7AND COM-
PRESSOR HARNESS CONNECTOR TER-
MINAL NO.j
1.
Continuity should exist.
If OK, check harness for short.
OK
CHECK POWER SUPPLY FOR A/C
RELAY.
Disconnect A/C relay.
Do approx. 12 volts exist between A/C
relay harness connector terminal Nos.j
1,
j6and ground?
Ye s
cNo
Check power supply circuit
and 10A or 20A (No.
)
located in the fuse block
(J/B).
Refer to EL section (ªWiring
Diagramº, ªPOWER SUP-
PLY ROUTINGº).
CHECK A/C RELAY AFTER DISCON-
NECTING IT.
Refer to HA-119 in Y61 SERVICE
MANUAL, publication No. SM7E-2Y61G1.
OK
cNG
Replace A/C relay.
jA(Go to next page.)
Note:
If the result is NG or No after checking circuit continuity, repair harness or
connector.
RHA399I
SHA579F
RHA653GA
RHA654G
.
.
.
.
.
.
TROUBLE DIAGNOSESAUTO
Magnet Clutch (Cont'd)
HA-4049
Page 529 of 579

jA
Reconnect A/C relay.
CHECK COIL SIDE CIRCUIT OF A/C
RELAY.
Do approx. 12 volts exist between ECM
harness connector terminal No.j
15and
ground?
Ye s
cNo
Disconnect A/C relay.
Disconnect ECM harness
connector.
Note
CHECK CIRCUIT CONTI-
NUITY BETWEEN A/C
RELAY HARNESS CON-
NECTOR TERMINAL NO.
j
2AND ECM HARNESS
CONNECTOR TERMINAL
NO.j
15.
Continuity should exist.
If OK, check harness for
short.
CHECK VOLTAGE FOR ECM.
Do approx. 12 volts exist between ECM
harness connector terminal No.j
21and
ground?
Ye s
cNo
CHECK ECM. Refer to EC
section.
Disconnect ECM harness connector.
Disconnect dual-pressure switch harness
connector.
Note
CHECK CIRCUIT CONTINUITY
BETWEEN ECM HARNESS CONNEC-
TOR TERMINAL NO.j
21AND DUAL-
PRESSURE SWITCH HARNESS CON-
NECTOR TERMINAL NO.j
2.
Continuity should exist.
If OK, check harness for short.
OK
CHECK DUAL-PRESSURE SWITCH.
Refer to HA-119 in Y61 SERVICE
MANUAL, publication No. SM7E-2Y61G1.
OK
cNG
Replace dual-pressure
switch.
jB
Note:
If the result is NG or No after checking circuit continuity, repair harness
or connector.
RHA400I
RHA401I
RHA402I
RHA403I
.
.
.
.
.
.
.
.
TROUBLE DIAGNOSESAUTO
Magnet Clutch (Cont'd)
HA-4050