This Preliminary Information communication advises the technician about vehicles that may have a inoperative radio with Diagnostic Trouble Code U0184 set in modules and unable to communicate with the radio using the scan tool. 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.
