Inspection Procedure

1. Put the vehicle in a no load test condition. Then set the headlights to high beam, set the heater blower switch to Hi, and run the engine at 2000 rpm. Using an electrical tester and probes, measure the current.
2. Using the intelligent tester or Techstream, read the Data List.
   1. Intelligent tester
      Fig 1: Measuring Current

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      ELEC PWR CTRL 

      DATA LIST REFERENCE (ELEC PWR CTRL)
      
      

      Item	Measurement Item / Display (Range)	Normal Condition	Diagnostic Note
      CHARGE CURRENT	Current battery current value display/ Min.: -300, Max.: 100 [A]	Amperage value is displayed	-

   2. Techstream

      Electric Power Control 

      DATA LIST REFERENCE (ELECTRIC POWER CONTROL)
      
      

      Item	Measurement Item / Display (Range)	Normal Condition	Diagnostic Note
      Electrical Charge Current	Current battery current value display/ Min.:-300, Max.: 100 [A]	Amperage value is displayed	-

      OK: Values of electrical tester and intelligent tester or Techstream are almost the same. 

NG: Go to step   4 

OK: GO TO NEXT STEP 

1. Disconnect the A49 sensor connector.
2. Measure the resistance according to the value(s) in the table below.

   Standard resistance 

   RESISTANCE SPECIFIED CONDITION
   
   

   Tester Connection	Condition	Specified Condition
   A49-1 (THB) - A49-4 (E2)	20 to 30°C (68 to 86°F)	1.5 to 2.1 kΩ
   	(0to70°C(32to158°F))	(0.3 to 6.0 kΩ)

   NOTE: The temperature shown in the inspection condition is for the area surrounding the sensor, not the sensor itself.

NG: REPLACE BATTERY CURRENT SENSOR ASSEMBLY (See  REMOVAL   ) 

Fig 2: Identifying A49 Sensor Connector Terminals With Resistance Graph

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: GO TO NEXT STEP 

1. Disconnect the A69 ECU connector.
2. Disconnect the A49 sensor connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard resistance 

   RESISTANCE SPECIFIED CONDITION
   
   

   Tester Connection	Condition	Specified Condition
   A69-20 (THB) - A49-1 (THB)	Always	Below 1 Ω
   A69-20 (THB) or A49-1 (THB) - Body ground	Always	10 kΩ or higher

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

Fig 3: Identifying A69 ECU And A49 Sensor Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: REPLACE PASSENGER SIDE JUNCTION BLOCK (ELECTRIC POWER CONTROL ECU) 

1. Disconnect the A49 sensor connector.
2. Measure the voltage according to the value(s) in the table below.

   Standard voltage 

   VOLTAGE SPECIFIED CONDITION
   
   

   Tester Connection	Switch Condition	Specified Condition
   A49-2(VC5)-A49-4(E2)	Engine switch on (IG)	4.5 to 5.5 V

OK: Go to step   6 

Fig 4: Identifying A49 Sensor Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: GO TO NEXT STEP 

1. Disconnect the A69 ECU connector.
2. Disconnect the A49 sensor connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard resistance 

   RESISTANCE SPECIFIED CONDITION
   
   

   Tester Connection	Condition	Specified Condition
   A69-6 (VC) - A49-2 (VC5)	Always	Below 1 Ω
   A69-10(E2)-A49-4(E2)	Always	Below 1 Ω
   A69-6 (VC) or A49-2 (VC5) - Body ground	Always	10 kΩ or higher
   A69-10(E2)or A49-4 (E2) - Body ground	Always	10 kΩ or higher

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

Fig 5: Identifying A69 ECU And A49 Sensor Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: REPLACE PASSENGER SIDE JUNCTION BLOCK (ELECTRIC POWER CONTROL ECU) 

1. Disconnect the A69 ECU connector.
2. Disconnect the A49 sensor connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard resistance 

   RESISTANCE SPECIFIED CONDITION
   
   

   Tester Connection	Condition	Specified Condition
   A69-9 (IB) - A49-3 (IB)	Always	Below 1 Ω
   A69-9(IB)or A49-3(IB)-Body ground	Always	10 kΩ or higher

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

Fig 6: Identifying A69 ECU And A49 Sensor Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: GO TO NEXT STEP 

1. Temporarily replace the battery current sensor with a new or normally functioning one (see REMOVAL  ).
2. Delete the DTC (see DTC CHECK / CLEAR  ).
3. Check for DTC again (see DTC CHECK / CLEAR  ).

   OK: No DTC is output. 

NG: REPLACE PASSENGER SIDE JUNCTION BLOCK (ELECTRIC POWER CONTROL ECU) 

OK: END (BATTERY CURRENT SENSOR IS DEFECTIVE)