EXPERTEC Technical Service Bulletins (93-I-6)

EXPERTEC TECHNICAL SERVICE BULLETINS

TECHNICAL SERVICE BULLETIN

APPLICATION

1993 Roadmasters built within the VIN breakpoints listed below:

• Arlington: 411630 through 412850
• Willow Run: 401886 through 402200

CONDITION

Higher than normal blower speeds will be experienced or selected by customers while in heater, defroster and air conditioning settings.

CAUSE

The heater shut off door may have failed and fallen into the heater air stream restricting flow, requiring higher blower speeds in automatic and manual systems.

CORRECTION

The repair procedure is to remove the broken heater shut off door as follows, which will allow proper temperature and flow of air.

1. Remove A/C Module Lower Evaporator Case per Service Manual, Section 1B1. Front screw "A" may be hidden by carpet and difficult to access. Use of a 7 mm flex head socket may be helpful. See Fig 1 for attaching points.
2. Locate heater shut off door in heater case (Fig. Fig 2 ).
3. If heater shut off door appears loose and NOT spring loaded, verify that it is broken by trying to cycle door. Do this by moving temperature lever from full cool to full warm on manual systems, or toggling temperature selector switch from full cool to full warm on automatic systems.
4. Pull heater shut off door hinge arm out of its socket at the end closest to the rear of the vehicle.
5. Remove heater shut off door by reaching through case opening and pushing the broken end of the door into the heater case cavity. Rotate the door while removing it through case opening.
6. Install/Connect A/C Module Lower Evaporator Case per Service Manual, Section 1B.

WARRANTY INFORMATION

Labor Operation: T3300

Labor Time: 0.9 Hr.