DTC B3A0B-18: A/C Heating Electric Expansion Valve Circuit Current Below Threshold [08/2023 - ]: Procedure

Pre-procedure1

• Disconnect the A56 heating electric expansion valve (No. 2 cooler expansion valve) connector.
• Disconnect the A61 heat pump ECU assembly connector.

• Measure the resistance according to the value(s) in the table below.

  Standard Resistance

  Tester Connection	Condition	Specified Condition	Result
  A56-1 (HV3) - A61-23 (HEA2)	Always	Below 1 Ω	Ω
  A56-4 (HV4) - A61-24 (HEA1)	Always	Below 1 Ω	Ω
  A56-5 (HV2) - A61-12 (HEB1)	Always	Below 1 Ω	Ω
  A56-2 (HV1) - A61-11 (HEB2)	Always	Below 1 Ω	Ω
  A56-1 (HV3) or A61-23 (HEA2) - Other terminals and body ground	Always	10 kΩ or higher	kΩ
  A56-4 (HV4) or A61-24 (HEA1) - Other terminals and body ground	Always	10 kΩ or higher	kΩ
  A56-5 (HV2) or A61-12 (HEB1) - Other terminals and body ground	Always	10 kΩ or higher	kΩ
  A56-2 (HV1) or A61-11 (HEB2) - Other terminals and body ground	Always	10 kΩ or higher	kΩ

  Result

  Proceed to
  OK
  NG

Post-procedure1

• None

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  2

Pre-procedure1

• Disconnect the A56 heating electric expansion valve (No. 2 cooler expansion valve) connector.

• Measure the resistance according to the value(s) in the table below.

  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

  *a	Component without harness connected (Heating Electric Expansion Valve (No. 2 Cooler Expansion Valve))

  Standard Resistance

  Tester Connection	Condition	Specified Condition	Result
  1 (HV3) - 4 (HV4)	20°C (68°F)	8 to 10 Ω	Ω
  2 (HV1) - 5 (HV2)	20°C (68°F)	8 to 10 Ω	Ω

  Result

  Proceed to
  OK
  NG

Post-procedure1

• None

Result: 

OK 

REPLACE HEAT PUMP ECU ASSEMBLY. Refer to  REMOVAL [08/2023 - ] 

Result: 

NG 

REPLACE HEATING ELECTRIC EXPANSION VALVE (NO. 2 COOLER EXPANSION VALVE). Refer to  REMOVAL [08/2023 - ]