Heater - Insufficient Heat to the Front Floor
HEATER - INSUFFICIENT HEAT TO THE FRONT Article No.
FLOOR - VEHICLES BUILT PRIOR TO 02/24/87 87-6-11
LIGHT TRUCK 1986-87 AEROSTAR
ISSUE: Vehicle occupants may experience discomfort in the front passenger compartment area when the Function Selector Lever is set in the HEAT position. The discomfort could be from excessive heat to the facial area because of air leaking through the instrument panel registers and/or insufficient heat to the front floor area because of excessive air bleed to the defrosters.
The causes for either or both conditions are the same:
1. Improper adjustment and/or routing of the function control cable (color-coded black).
2. Kinks, binds, or permanent damage to the function control cable.
3. A restriction felt as the Function Selector Lever is moved through its course of travel.
ACTION: Check and correct any function control cable difficulties including adjustment, routing, and performance. Check for any restrictions in control lever movement. If it is determined that the vent/heat door is binding in the plenum, replace the door (E69Z- 18A559-B) according to the procedure published in TSB Article No. 86-9-15, dated May 7, 1986.
If the condition persists after checking and servicing the control cable and determining that the vent/heat door is not binding, the plenum assembly must be replaced with a new plenum (E69Z-18471-C). The procedure for plenum assembly replacement is covered below.
Figure 10 - Article 87-6-11:
PLENUM ASSEMBLY REMOVAL AND INSTALLATION
Removal
1. Refer to Figure 10, heater plenum assembly and floor duct removal.
2. Disconnect the battery ground cable.
3. Drain the coolant from the cooling system.
4. Disconnect the heater hoses from the heater core tubes using Heater Hose Disconnect Tool T85T-18539-AH to depress the plastic locking tabs in the hose coupling retainer. (The procedure involved in using Tool T85T-18539- AH to disconnect and connect a heater hose with a snap-lock fitting is covered in Section 18-06 of the Aerostar Shop Manual.)
5. Remove the instrument panel following the procedure provided in Steps 2 through 11 in TSB Article No. 86-9-15. (instead of loosening the panel, as directed in Step 12 of the TSB, remove it.)
6. Remove the left hand floor duct by removing the screw which attaches the floor duct to the dash panel.
7. Remove four (4) nuts which secure the plenum to the passenger side of the dash panel. Remove the plenum.
Installation
1. Position the plenum against the dash panel. Align it with the attaching studs in the dash panel.
2. Secure the plenum with four (4) attaching nuts.
3. Install the floor duct by attaching it to the dash panel with its one attaching screw.
4. Install the instrument panel following the procedure provided in TSB Article No. 86-9-15.
5. Install the heater hoses on the heater core tube. Use new O-rings in the coupling and replacements for the retainer and spacer if they should be damaged.
6. Refill the system with coolant.
7. Connect the battery ground cable.
8. Check the A/C system for proper performance.
PART NUMBER PART NAME CLASS
E69Z-18A559-B Vent/Heat Door C
E69Z-18471-C Plenum Assembly C
OTHER APPLICABLE ARTICLES: 86-9-15, Supersedes 86-21-13
WARRANTY STATUS: Reimbursable within the provisions of the Warranty and Policy Manual
OPERATION: SP870611A
TIME: 3.3 Hrs. DLR. CODING: Basic Part No. 18A559 -
Code: 41