TROUBLE DIAGNOSES — Wiring Diagram – Heater / Main Power Supply and Ground Circuit Check

HA-44wiring diagram

Continued from HA-43

Wiring Diagram — Heater

Heater wiring diagram

Components (10)

eccs_control_unitjoint_f22fuse_blockign_acc_onjoint_m54blower_motorfan_switchblower_resistorjoint_m10joint_m56

Connections (10)

ign_acc_on

ign_acc_onfuse_block:15A_IGN_ACC_ON??

fuse_block

fuse_block:15A_IGN_ACC_ONblower_motorL/R

blower_motor

blower_motorfan_switch:1B

fan_switch

fan_switch:5blower_resistorL/R

fan_switch:4blower_resistorL/B

fan_switch:3blower_resistorL/Y

fan_switch:2joint_m10B

fan_switch:2joint_m56B

eccs_control_unit

eccs_control_unitjoint_f22LG/R— (E.F.I. harness)

joint_f22

joint_f22joint_m54LG/R— (Main harness)

Main Power Supply and Ground Circuit Check

POWER SUPPLY CIRCUIT CHECK FOR A/C SYSTEM

Check power supply circuit for air conditioning system. Refer to "POWER SUPPLY ROUTING" in EL section and A/C ELECTRICAL CIRCUIT.

THERMO CONTROL AMP. CHECK

Check power supply circuit for thermo control amp. with ignition switch ON.

Thermo control amp. power-supply voltage check

1
Disconnect thermo control amp. harness connector.
RHA439D
2
Connect voltmeter from harness side.
3
Measure voltage across terminal No. 34 and body ground.

Thermo control amp. — voltage measurement

Voltmeter terminal (+)	Voltmeter terminal (−)	Voltage
34	Body ground	Approx. 12 V

Voltmeter terminal (−)Body ground

VoltageApprox. 12 V

Check body ground circuit for thermo control amp. with ignition switch OFF, A/C switch ON and fan switch ON.

Thermo control amp. body-ground continuity check

1
Disconnect thermo control amp. harness connector.
RHA440D
2
Connect ohmmeter from harness side.
3
Check for continuity between terminal No. 22 and body grond.

Thermo control amp. — continuity measurement

Ohmmeter terminal (+)	Ohmmeter terminal (−)	Continuity
22	Body ground	Yes

Ohmmeter terminal (−)Body ground

ContinuityYes

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