GM Service Manual Online
For 1990-2009 cars only

Symptom/DTC

Diagnostic Table

DTC B0768

DTC B0768 Service Indicator Circuit High

DTC B2725

DTC B2725 ATC Mode Switch Circuit Malfunction

DTC C0300

DTC C0300 Rear Speed Sensor Malfunction

DTC C0305

DTC C0305 Front Speed Sensor Malfunction

DTC C0308

DTC C0308 Motor A/B Circuit Low

DTC C0309

DTC C0309 Motor A/B Circuit High

DTC C0310

DTC C0310 Motor A/B Circuit Open

DTC C0315

DTC C0315 Motor Ground Circuit Open

DTC C0323

DTC C0323 T-Case Lock Circuit Low

DTC C0324

DTC C0324 T-Case Lock Circuit High

DTC C0327

DTC C0327 Encoder Circuit Malfunction

DTC C0357

DTC C0357 Park Switch Circuit High

DTC C0362

DTC C0362 4LO Discrete Output Circuit High

DTC C0367

DTC C0367 Front Axle Control Circuit High

DTC C0374

DTC C0374 General System Malfunction

DTC C0376

DTC C0376 Front/Rear Shaft Speed Mismatch

DTC C0387

DTC C0387 Unable to Perform Shift

DTC C0550

DTC C0550 ECU Malfunction

DTC C0611

DTC C0611 VIN Information Error

U-Code DTC

Refer to the applicable table in Data Link Connector (DLC) in Electrical Diagnosis