Page 2657 of 3051
10 CHECK POWER SUPPLY FOR HEATER CONTROL PANEL (A/C SWITCH)
Do approx. 12 volts exist between heater control panel harness terminal No. 7 and body ground?
NHA472
YesorNo
Ye s©GO TO 12.
No©+For Europe: GO TO 11.
11 CHECK CIRCUIT CONTINUITY BETWEEN HEATER CONTROL PANEL AND ECM
Check circuit continuity between heater control panel harness terminal No. 7 and ECM harness terminal No. 44.
NHA473
Continuity should exist.
If OK, check harness for short.
OK or NG
OK©Check ECM. Refer to EC-134 (QG), EC-659 (SR),“ECM Terminals and Reference
Value”.
NG©Repair harness or connector.
TROUBLE DIAGNOSES
Magnet Clutch (Cont’d)
HA-66
Page 2658 of 3051
12 CHECK HEATER CONTROL PANEL CIRCUIT
Check circuit continuity between heater control panel harness terminal No. 8 and 18.
NHA474
Continuity should exist.
If OK, check harness for short.
OK or NG
OK©GO TO 13.
NG©Repair harness or connector.
13 CHECK CIRCUIT CONTINUITY BETWEEN ECM AND HEATER CONTROL PANEL
Check circuit continuity between ECM harness terminal No. 51 and heater control panel harness terminal No. 18.
NHA427
Continuity should exist.
If OK, check harness for short.
OK or NG
OK©GO TO 14.
NG©Repair harness or connector.
14 CHECK FAN SWITCH
Refer to HA-61.
YesorNo
Ye s©GO TO 15.
No©Replace heater control panel.
TROUBLE DIAGNOSES
Magnet Clutch (Cont’d)
HA-67
Page 2659 of 3051
15 CHECK BODY GROUND CIRCUIT
Check circuit continuity between heater control panel harness terminal No. 13 and body ground.
NHA428
Continuity should exist.
If OK, check harness for short.
OK or NG
OK©INSPECTION END
NG©Repair harness or connector.
TROUBLE DIAGNOSES
Magnet Clutch (Cont’d)
HA-68
Page 2660 of 3051
MAGNET CLUTCH CIRCUIT (FOR YD ENGINE)=NLHA0203SYMPTOM:
+Magnet clutch does not engage when A/C switch and fan
switch are ON.
1 CHECK POWER SUPPLY FOR COMPRESSOR
Disconnect compressor harness connector.
Do approx. 12 volts exist between compressor harness terminal No. 1 and body ground?
NHA419
YesorNo
Ye s©GO TO 2.
No©Disconnect A/C relay. GO TO 3.
2 CHECK MAGNET CLUTCH COIL
OK or NG
NG©Replace magnet clutch.Refer to HA-92
3 CHECK CIRCUIT CONTINUITY BETWEEN A/C RELAY AND COMPRESSOR HARNESS
Check circuit continuity between A/C relay harness terminal No. 3 and compressor harness terminal No. 1.
NHA420
Continuity should exist.
If OK, check harness for short.
OK or NG
OK©GO TO 4.
NG©Repair harness or connector.
TROUBLE DIAGNOSES
Magnet Clutch (Cont’d)
HA-69
Page 2661 of 3051
4 CHECK POWER SUPPLY FOR A/C RELAY
Disconnect A/C relay.
Do approx. 12 volts exist between A/C relay harness terminal Nos. 1, 5 and body ground?
RHA635H
YesorNo
Ye s©GO TO 5.
No©Check power supply circuit and 10A (No. 15) fuse at fuse block. Refer to EL-10,“Wiring
Diagram—POWER—”.
5 CHECK A/C RELAY AFTER DISCONNECTING IT
Refer to HA-73.
OK or NG
OK©Reconnect A/C relay. GO TO 6.
NG©Replace A/C relay.
6 CHECK COIL SIDE CIRCUIT OF A/C RELAY
Do approx. 12 volts exist between ECM harness terminal No. 204 and body ground?
NHA429
YesorNo
Ye s©GO TO 8.
No©Disconnect A/C relay. Disconnect ECM harness connector. GO TO 7.
TROUBLE DIAGNOSES
Magnet Clutch (Cont’d)
HA-70
Page 2662 of 3051
7 CHEC KCIRCUI TCONTINUIT YBETWEE NA/C REL AY AN DEC MHARNESS
NHA430
8 CHEC KVO LTAG EFO RECM
NHA431
9 CHEC KPOWE RSUPP LY FO RDUAL-PRESSUR ESWITCH
NHA432
Magne tClutc h(Cont ’d)
Page 2663 of 3051
10 CHECK DUAL-PRESSURE SWITCH
Refer to HA-74.
OK or NG
OK©GO TO 11.
No©Replace dual-pressure switch.
11 CHECK CIRCUIT CONTINUITY BETWEEN DUAL-PRESSURE SWITCH AND HEATER CONTROL PANEL
(A/C SWITCH)
Check circuit continuity between dual-pressure switch harness terminal No. 1 and heater control panel harness terminal
No. 7.
NHA475
Continuity should exist.
If OK, check harness for short.
OK or NG
OK©GO TO 12.
NG©Repair harness or connector.
12 CHECK A/C SWITCH
Refer to HA-74.
OK or NG
OK©GO TO 13.
NG©Replace A/C switch.
13 CHECK HEATER CONTROL PANEL CIRCUIT
Check circuit continuity between heater control panel harness terminal No. 8 and No. 18.
NHA474
Continuity should exist.
If OK, check harness for short.
OK or NG
OK©GO TO 14.
NG©Repair harness or connector.
TROUBLE DIAGNOSES
Magnet Clutch (Cont’d)
HA-72
Page 2664 of 3051
14 CHECK FAN SWITCH
Refer to HA-61.
OK or NG
OK©GO TO 15.
NG©Replace fan switch.
15 CHECK BODY GROUND CIRCUIT
Check circuit continuity between heater control panel harness terminal No. 13 and body ground.
NHA428
Continuity should exist.
If OK, check harness for short.
OK or NG
OK©INSPECTION END.
NG©Repair harness or connector.
RHA638H
ELECTRICAL COMPONENT INSPECTIONNLHA0192A/C RelayNLHA0192S01Check continuity between terminal Nos. 3 and 5.
Conditions Continuity
12V direct current supply between terminal Nos. 1 and 2 Yes
No current supply No
If NG, replace relay.
TROUBLE DIAGNOSES
Magnet Clutch (Cont’d)
HA-73