DTC P0A1F-150: Battery Energy Control Module; DTC P0A1F-157: Battery Energy Control Module: Procedure

1. Turn the power switch off.
2. Measure the voltage according to the value(s) in the table below.

   Standard voltage

   Tester Connection	Condition	Specified Condition
   Auxiliary battery positive terminal (+) - Auxiliary battery negative terminal (-)	68°F (20°C)	11 to 14 V

NG → CHARGE OR REPLACE AUXILIARY BATTERY 

OK: Go to next step 

1. Turn the power switch on (IG).
2. Measure the voltage according to the value(s) in the table below.
   Fig 1: Identifying ZR2 Connector Terminal

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   Standard voltage

   Tester Connection	Switch Condition	Specified Condition
   zR2-1 (IGCT) - zR2-20 (GND)	Power switch on (IG)	8.6 V or higher

   HINT: 

   • For the removal and installation procedures related to the battery pack wire inspection. Refer to REMOVAL .
   • Perform this inspection with the battery pack wire connected.

NG → See step   4 

OK: Go to next step 

1. Turn the power switch off.
   Fig 2: Checking Harness And Connector (Battery Pack Wire Connector -- Battery Smart Unit)

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2. Disconnect the battery pack wire connector.
3. Disconnect connector z36 from the battery smart unit.

   HINT: 

   For the removal and installation procedures related to the battery smart unit. Refer to REMOVAL .

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

   Standard resistance

   Tester Connection	Switch Condition	Specified Condition
   zR2-1 (IGCT) - z36-1 (IGCT)	Power switch off	Below 1 Ω

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   7 

1. Remove the IGCT3 fuse from the luggage room junction block assembly.
   Fig 3: Identifying IGCT3 Fuse

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

   Standard resistance

   Tester Connection	Condition	Specified Condition
   IGCT3 fuse terminals	Always	Below 1 Ω

NG → REPLACE FUSE (IGCT3 FUSE) 

OK: Go to next step 

1. Remove the IGCT2 NO. 2 fuse from the engine room No. 3 relay block.
   Fig 4: Identifying IGCT2 NO. 2 Fuse

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

   Standard resistance

   Tester Connection	Condition	Specified Condition
   IGCT2 NO. 2 Fuse Terminals	Always	Below 1 Ω

NG → REPLACE FUSE (IGCT2 NO. 2 FUSE) 

OK: Go to next step 

1. Disconnect the battery pack wire connector.
   Fig 5: Locating Battery Pack Wire Connector

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2. Install the IGCT3 fuse to the luggage room junction block assembly.
   Fig 6: Identifying IGCT3 Fuse

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3. Install the IGCT2 NO. 2 fuse to the engine room No. 3 relay block.
   Fig 7: Identifying IGCT2 NO. 2 Fuse

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4. Remove the IGCT2 relay from the engine room No. 2 relay block.
5. Measure the resistance according to the value(s) in the table below.
   Fig 8: Identifying Battery Pack Wire Connector & Engine Room No. 2 Relay Block

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard resistance

   Tester Connection	Switch Condition	Specified Condition
   zR2-1 (IGCT) - Engine room No. 2 relay block IGCT2 relay terminal 3	Power switch off	Below 1 Ω

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → CHECK AND REPAIR POWER SOURCE CIRCUIT (IGCT2 RELAY)