Information Bus

For diagnosis of the following codes, begin with Test 1A - Bus Failure Messages 1A Bus Failure Messages

Short to Battery: Either or both of the bus wires are shorted to the battery potential.

Short to 5 Volts: Either or both of the bus wires are shorted to a 5-volt potential.

Short to Ground: Either or both of the bus wires are shorted to ground.

Bus (+) & Bus (-) Shorted Together: The two bus wires are shorted together.

No Termination: The bus system has lost connection with all of its terminators.

Bus Bias Level too Low: Either or both of the bus wire potentials are significantly below their normal 2.5 volts.

Bus Bias Level too High: Either or both of the bus wire potentials are significantly above their normal 2.5 volts.

No Bus Bias: The bus system has lost connection with all modules that provide bias.

Bus (+) Open: The bus (+) wire has lost connection with termination and/or bias.

Bus (-) Open: The bus (-) wire has lost connection with termination and/or bias.

Not Receiving Bus Messages Correctly: The DRB cannot communicate over the bus and does not know why.