ECU Power Source Circuit [07/2015 - ]: Procedure

1. Disconnect the H188 driving support ECU assembly connector.

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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	Condition	Specified Condition
   H188-7 (B) - Body ground	Engine switch on (IG)	11 to 14 V

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   *a	Front view of wire harness connector (to Driving Support ECU Assembly)

4. Turn the engine switch off.
5. Reconnect the H188 driving support ECU assembly connector.

Result:  NG

NG 

REPAIR OR REPLACE POWER SOURCE CIRCUIT 

Result:  OK

OK 

See step  2

1. Disconnect the H188 driving support ECU assembly connector.
2. Measure the resistance according to the value(s) in the table below.

   Standard Resistance (Check for Open)

   Tester Connection	Condition	Specified Condition
   H188-28 (GND) - Body ground	Always	Below 1 Ω

3. Reconnect the H188 driving support ECU assembly connector.

Result:  OK

OK 

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE 

(Refer to PROBLEM SYMPTOMS TABLE [07/2015 - ] )

Result:  NG

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR