A/C - Improper Temperature Control

89Oldsmobile09

SUBJECT: IMPROPER TEMPERATURE CONTROL IN DRIVER SELECTED LOWER OR UPPER MODE AIR DELIVERY (REPLACE PROM)

MODELS/YEARS: 1986-88 TORONADO
NUMBER: 88-T-144

CORP. REF. NO: 911203

DATE: June 1989

SECTION: 1C, 8D
Some 1986-1988 Toronados may exhibit a condition where the discharge air temperature does not control properly when the forced upper mode or forced lower mode settings on the control panel are selected. Should this condition occur the symptoms are:

^ Discharge air from the A/C outlets becomes too warm when the forced upper mode is selected.

^ Discharge air from the heater outlet becomes too cold when the forced lower mode is selected.

This condition may be due to the calibration value for the forced upper and lower modes within the BCM PROM. To repair this condition enter diagnostics as outlined in Section 8D of the Service Information Manual to check the BCM PROM I.D. and replace, if necessary, with the new part number from the table below:

Old New
PROM PROM
Model I.D. New P/N I.D.

1986 Toronado 6763 16124160 4163
1987 Toronado 5453 16124161 4173
1988 Toronado 173 16121073 1053
(before VIN JU309680)

Parts are currently available from GMSPO.

Warranty Information to Replace PROM:

Labor Operation Number: N4801
Labor Time: .5 hrs.