B1000 - ECU Malfunction

Diagnostic Chart:

CIRCUIT DESCRIPTION
The DTC B1000 is an internal microprocessor malfunction of the Vehicle Interface Unit (VIU) and cannot be repaired. If the VIU power and ground circuits are operating normally and the B1000 code is current and cannot be cleared, then the VIU must be replaced.

CONDITIONS FOR RUNNING THE DTC
The ignition must be in the Run or ACC position and the VIU power must be on. The VIU will run this internal test every 300 msec. Battery voltage must be at least 9.5 volts and no more that 15.5 volts.

CONDITIONS FOR SETTING THE DTC
The VIU is unable to communicate with the GPS module for 10 seconds.

ACTION TAKEN WHEN THE DTC SETS
When the DTC is current, the VIU sees all information received from the Global Positioning System (GPS) module as Invalid.

CONDITIONS FOR CLEARING THE DTC
The VIU is able to communicate with the GPS module.

TEST DESCRIPTION
The number(s) below refer to the step number(s) on the diagnostic table.
2. Determines that all connections are good for the VIU harness