GM Service Manual Online
For 1990-2009 cars only

Diagnostic Trouble Code

Description

Action

Important: The DTCs listed below are in order of importance. Diagnose the DTCs in the same order

U1016 Current

Loss of Class 2 Communication with VCM

Scan Tool Does Not Communicate with Components in Data Link Communications

U1255 Current

Class 2 Communication Malfunction

Scan Tool Does Not Communicate with Components in Data Link Communications

C0559 Current

EEPROM Checksum Error

DTC C0559 EEPROM Checksum Error

B2947 Current

Security System Sensor Power Circuit Low

DTC B2947 Security System Sensor Power CKT Low

B3033 Current

Security System Indicates Tamper

DTC B3033 Security System Indicates Tamper

B2960 Current

Security System Sensor Data Incorrect But Valid

DTC B2960 Sec Sys Sensor Data Incorrect but Valid

B2957 Current

Security System Sensor Data Circuit Low

DTC B2957 Security System Sensor Data Circuit Low

B2958 Current or History

Security System Sensor Data Circuit High

DTC B2958 Security System Sensor Data Circuit High

B2948 Current

Security System Sensor Power Circuit High

DTC B2948 Security System Sensor Power CKT High

B3031 CUrrent

Security System Controller in Learn Mode

DTC B3031 Security System Controller in Learn Mode

B0688 Current

Security System Indicator Circuit High

DTC B0688 Security System Indicator Circuit High