DTC B2620: ECU Power Source Circuit Malfunction: Procedure

1. Disconnect the J28 connector from the multiplex tilt and telescopic ECU.
   Fig 1: Identifying Multiplex Tilt And Telescopic ECU Connector Terminals

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

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   J28-9 (ECUB) - Body ground	Always	11 to 14 V

NG → See step   3 

OK: Go to next step 

1. Measure the resistance according to the value(s) in the table below.
   Fig 2: Identifying Multiplex Tilt And Telescopic ECU Connector Terminals

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   Standard Resistance

   Tester Connection	Condition	Specified Condition
   J28-11 (GND) - Body ground	Always	Below 1 Ω

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   4 

1. Disconnect the RA connector from the main body ECU RH (cowl side junction block RH).
   Fig 3: Identifying Multiplex Tilt And Telescopic ECU And Main Body ECU Terminals

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

   Standard Resistance

   Tester Condition	Condition	Specified Condition
   J28-9 (ECUB) - RA-18	Always	Below 1 Ω
   J28-9 (ECUB) - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (MULTIPLEX TILT AND TELESCOPIC ECU - MAIN BODY ECU RH) 

OK → REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - MAIN BODY ECU RH)