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A/C B446, B447, and B448 (Low Refrigerant Codes) Set

90caddy10
Bulletin No. T-90-101
File in Group 8
Number 118
Corp. Ref. No. 018114
Date Aug. 1990

SUBJECT: B446, B447, AND B448 CODE DIAGNOSIS

MODELS AFFECTED: 1986-1990 ELDORADOS AND SEVILLES

Figure 1 - Low Refrigerant Charge:




Figure 2 - Low Temperature Pressure:




Figure 3:




Some 1986-1990 Eldorados and Sevilles may experience low refrigerant codes showing a code B446, codes B446 and B447, or code B448. To diagnose and repair these conditions follow the appropriate trouble tree in Figure 1, Figure 2, and/or Figure 3.

On 1988-1990 vehicles a premature low refrigerant code B446/B447 may be displayed in cool ambients (45~ - 65~ F). This condition can be repaired by following the trouble tree (Figure 1) for diagnosis and, if necessary, replacing the PROM in accordance with the chart below:



PROM CHART
NOTE: Failure to recover, evacuate, and recharge with the proper amount of refrigerant may result in recurrence of low refrigerant indicator.



NOTE: Add .7 hour for recovery, evacuation, and recharge of A/C system when necessary.

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