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: Example 3 DTCs Stored In 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 lines and check the bus lines for an open circuit.
See appropriate System Wiring Diagram article.

Fig 2: Schematic - Control Modules Connected Across Bus Lines

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

Fig 3: Schematic - Checking Bus Lines For Short Circuit

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