ECU Power Source Circuit: Procedure

1. Disconnect the TCM connector.
   Fig 1: TCM Connector Terminal Identification

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2. Turn the engine switch on (IG).
3. Measure the voltage according to the value(s) in the table below.

   Standard voltage

   Tester Connection	Switch Condition	Specified Condition
   B40-18 (+B) - B40-8 (E1)	Engine switch on (IG)	9 to 14 V

OK → CHECK FOR INTERMITTENT PROBLEMS 

NG: Go to next step 

1. Measure the resistance according to the value(s) in the table below.
   Fig 2: TCM Connector Terminal Identification

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   Standard resistance

   Tester Connection	Condition	Specified Condition
   B40-8 (E1) - Body ground	Always	Below 1 Ω

2. Reconnect the TCM connector.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (TCM - BODY GROUND) 

OK → REPAIR OR REPLACE HARNESS OR CONNECTOR (TCM - EFI RELAY)