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Programmer, Link & Temperature Door

With engine at normal operating temperature, idling, and A/C system operating, proceed as follows:

  1. Loosen hex screw of door link at output shaft of programmer. Place control head selector in "DEF" position. Remove electrical connector from ambient sensor; this results in proper positioning of output shaft in programmer (full heat position).
  2. Make sure air mix door is in full heat position. Blower air flow will now hold mix door in proper position. Without disturbing door link or output shaft position, tighten hex screw on door link.
  3. Check for proper adjustment as follows: Connect tester J-23678 into wiring harness and programmer, using harness adapter J-24774 and J-24774-75. Place control head selector in "AUTO". Place the tester Manual-Automatic switch in "MANUAL". Using the Manual Control, swing programmer to "MAX HEAT" and then to "MAX COLD". High blower speed should be obtained in both positions.
  4. Now check for recirculation operation: Operate system with Manual Control on "150" for 5 minutes so restricted vacuum line can move the outside air door to outside air position. With control head selector at "HI", move Manual Control to "MAX COLD". With all doors and windows closed, blower noise level should increase when recirculation occurs (approximately 3 minute delay due to restrictor).
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