This Preliminary Information communication provides information to the technician about vehicles that have an inoperative radio. Technician may find Diagnostic Trouble Code U0184 stored in multiple modules. If the concern is present at the dealership technician will need to contact General Motors Technical Assistance Center for further assistance if within 4 hours from Warren, Michigan. Technician should remove power from the radio. If the radio starts working with a power cycle advise the customer that we apologize for this inconvenience and that General Motors is working on a permanent solution for this concern. After the power cycle and the radio is still inoperative record the radio power and ground readings and the voltage on the low speed data line.
