RADIO DISPLAYS INCORRECT DEFECTIVE EEPROM

VEHICLES AFFECTED: 1986 Riviera

1986 Rivieras below VIN GU401975 with UX1 graphic equalizer radios can display an incorrect graphic control centre (GCC) summary page on approximately 5% of ignition cycles. The summary page is missing the graphic equalizer and balance keys.

To determine if a vehicle has this problem, with the ignition 'off', disconnect and then reconnect the car battery; then turn the ignition 'on', and if the graphic equalizer and balance keys are missing from the summary page of the GCC, the EEPROM of the BCM is defective (see Figure 1). A normal GCC summary page is shown in Figure 2.

Refer to bulletin 86-8-120 for the correct procedures to obtain an exchange EEPROM. Remember to include the vehicle mileage.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.