GM Service Manual Online
For 1990-2009 cars only

ECC - EXCESSIVE HEAT ADJUST AIR MIX VALVE

MODELS AFFECTED: 1985-1987 DE VILLE, FLEETWOOD 1986-1987 ELDORADO, SEVILLE 1987 ALLANTE

Some 1985 through 1987 De Villes and Fleetwoods, 1986 through 1987 Eldorados and Sevilles and 1987 Allantes may experience an excessive heating condition. This condition may be a result of a misadjusted air mix valve or excessive air mix valve lever play. The following steps should be taken to repair this condition.

1. Remove the glove box to gain access to the programmer, air mix valve link and lever, Figure 1.

2. With the ignition in thp"ON" position, set the Electronic Climate Control panel to auto and 90 DEG F. Allow ample time for the programmer arm to travel to its maximum heat position.

3. Snap the air mix connecting link out of the plastic retainer on the programmer output arm. Check the air mix valve for free travel (push valve to maximum A/C position and check for possible binding).

4. Check the air mix lever for an improper press fit by attempting to lift the lever upward. If any movement is present, the flat face of the rod must be shimmed to eliminate the play, Figure 1.

5. Pre-load the air mix valve in the maximum heat position by pulling the threaded air mix valve link to ensure the valve is sealing.

6. Snap the threaded air mix valve link into the plastic retainer on the programmer arm. Take care to avoid influencing the programmer arm or air mix valve position.

7. Set the temperature setting on the Efectronic Climate Control panel to 60 DEG F. Check to verify that the programmer arm and air mix valve travels to the max A/C position.

For warranty purposes, use Labor Operation number D1855 for .3 hour to adjust the air mix valve, or Labor Operation T6228 at .4 hours to shim the air mix lever.


Object Number: 81723  Size: FS

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.