ECC A/C - Erratic Mode Change

91cadillac04

Bulletin No.: T-91-88
File in Group: 1
Number: 77
Corp. Ref. No.: 116801
Date: May, 1991


SUBJECT:
ERRATIC ECC MODE CHANGE OR CRUISE CONTROL UNABLE TO MAINTAIN SET SPEED ON HILLS

MODELS AFFECTED:
1990-1991 ELDORADOS AND SEVILLES

Figure 1 - Disconnected Vacuum Hose:

Some 1990-1991 Eldorados and Sevilles may experience erratic Electronic Climate Control (ECC) mode change or cruise control may be unable to maintain set speed on hills due to a disconnected vacuum hose from the vacuum reserve tank. Refer to Figure 1. The hose may become disconnected from a snow or ice build up in the front wheel well area or during an underbody car wash.

Figure 2 - Vacuum Tank Connection:

To repair this condition ensure that the connection is fully seated as shown in Figure 2.

For warranty purposes use Labor Operation T6546 at .2 hour.