Engine Controls - DTC P0600, B0221 and/or B0223
NUMBER: 11-81-06DATE: 11/16/06
APPLICABILITY:
2005MY~06MY Legacy/Outback equipped with H4 and H6
2006MY B9 Tribeca
SUBJECT:
Diagnostic Trouble Codes (DTC) P0600, B0221 and/or B0223
(Codes for communication error)
INTRODUCTION
This service bulletin explains how to diagnose P0600, B0221, and/or B0223 effectively, avoiding unnecessary diagnostics. When the communication system of the vehicle becomes unstable, multiple trouble codes and multiple problem phenomena may occur.
REPAIR PROCEDURE INFORMATION
There are 6 patterns for the combination of trouble codes and problem phenomena listed in the chart (located in this bulletin).
For example, Pattern 1 on the chart is showing you that DTC B0221, BO223, and P0600 exist and problem phenomena are Check Engine Light ON, VDC light ON, Coolant Temperature Meter indicates maximum, Odometer indicates "Er Hc", Cruise Control is cancelled and Cruise Control Lamp blinks.
Pattern 5 is showing you that DTC B0221 exists and problem phenomena are, Coolant Temperature Meter indicates maximum and the Odometer indicates "Er Hc".
TECHNICAL EXPLANATION
The Body Integrated Control Unit (BIU) monitors whole communication lines and it detects communication errors/troubles. When it detects problems, the system goes to fail safe mode and displays Check Engine Light ON, VDC light ON, Coolant Temperature Meter indicates maximum, Odometer indicates "Er Hc", Cruise Control is cancelled and Cruise Control Lamp blinks to avoid the problem from becoming more severe. B0221, B0223, P0600 are resultant codes.
To avoid a severe system abnormality, the BW monitors communication instability in a very short time period. The communication system may become unstable under the following circumstances:
^ Near powerful radio equipment, such as truck radios
^ Poor contact on connectors
^ Noises emitted by non-genuine accessories or modified electrical circuits
^ Unstable battery voltage due to non-genuine accessories or modified electrical circuits
^ Starting the engine when battery is weak
^ Repeating ignition switch ON and OFF quickly or repeating engine starting and stopping
In these cases, communication stability can be restored by the self-recovery function, but the malfunction display and fail-safe mode continue to alert the driver until the ignition switch is turned off.
TROUBLESHOOTING FLOW CHART
Check for DTC(s) and vehicle condition.
If any of the steps 2 through 6 direct you to "Yes", and you are able to repair the problem, this is not a temporary unstable communication phenomenon.
Disclaimer