Diagnostic Aids

If DTC B1982 or B1983 are set as current, DTC B0533 will not set. Instead a Class 2 message will be sent to PCM that percentage of ignition 1 voltage is too low. Check for short to voltage in Purple or Purple/White wire between Platform Zone Module (PZM) and fuel level sensor. If circuit is okay, and DTC B0533 is set as current, replace PZM. See REMOVAL & INSTALLATION in BODY CONTROL MODULES - ELDORADO article. If circuit is okay, and DTC B0533 is set as history, replace fuel level sensor. See FUEL LEVEL SENSOR  under REMOVAL & INSTALLATION.