LS 430 V8-4.3L (3UZ-FE) (2002)
b. Check the continuity with ground.
1. Disconnect connectors "A" and "C" and measure the resistance between terminal 1 and 2 connector "A" and body ground.
Resistance: 1 MOhm or higher
HINT: Measure the resistance while lightly shaking the wire harness vertically and horizontally.
In the case of Fig. 6:
Between terminal 1 of connector "A" and body ground Continuity (short)
Between terminal 2 of connector "A" and body ground -> No continuity
Therefore, it is found out that there is a short circuit between terminal 1 of connector "A" and terminal 1 of connector "C".
2. Disconnect connector "B" and measure the resistance between terminal 1 of connector "A" and body ground, and terminal 1 of connector
"B2" and body ground.
In the case of Fig. 7:
Between terminal 1 of connector "A" and body ground -> No continuity
Between terminal 1 of connector "B2" and body ground -> Continuity (short)
Therefore, it is found out that there is a short circuit between terminal 1 of connector "B2" and terminal 1 of connector "C".
4. CHECK AND REPLACE ECU
NOTE:
-
Start an inspection of the connector from the backside of the connector in the wire harness side with the connector connected to the ECU.
-
When a measuring condition is not specified, perform the inspection with the engine stopped and also the ignition switched ON.
a. First check the ECU ground circuit. If it is faulty, repair it. If it is normal, the ECU could be faulty, so replace the ECU with a normal
functioning one and check that the symptoms appear.