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For 1990-2009 cars only

CLOCK GAINS OR LOSES TIME INTERMITTENTLY

MODELS AFFECTED: 1988-1989 ELDORADOS AND SEVILLES

Clocks on some 1988-1989 Eldorados and Sevilles may gain or lose time intermittently. The amount of time may vary from a few minutes to several hours.

IMPORTANT: A normally operating clock may lose or gain up to two minutes per month.

To repair this condition check the PROM I.D. and install the appropriate new PROM using the following procedure:

1. Determine the amount of time gained or lost. If it is less than two minutes over a one-month period, the clock is operating properly.

2. Determine whether the trip odometer or climate control setting is affected, or if a BCM code B552 is set. If so, refer to the Service Information Manual for BCM power and ground diagnosis.

3. Check PROM I.D. (BD99). Refer to Section 8D of the Service Information Manual.

4. If the PROM I.D. is: 1988 - 0186 or 8256 1989 - 3766 or 3426 Replace the EPROM with: 1988 - P/N 16139065 PROM I.D. 9066 1989 - P/N 16138881 PROM I.D. 8766

5. If the PROM I.D. is not: 1988 - 0186 or 8256 1989 - 3766 or 3426

Refer to the Service Information Manual for BCM power and ground diagnosis. All parts are currently available from GMSPO.

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.