Example 3:

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Using the DTCs stored in the memories, you have determined that none of the control modules are sending or receiving signals.

Fig 1: DTC Memory - None Of The Control Modules Are Sending Or Receiving Signals

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Switch ignition off.
Disconnect the control modules connected across the bus wires and check for short circuits between the bus wires.
See appropriate System Wiring Diagram article.

Fig 2: Schematic - Checking For Short Circuits Between Bus Wires

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Check the bus wires for short circuit to B+ or Ground (GND).

Fig 3: Schematic - Checking Bus Wires For Short Circuit To B+ Or Ground

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