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Testing The FLEETWOOD Rear System: Notes

The complete test procedure requires the use of Automatic Climate Control Tester J-21512 and encompasses seven different steps. For ease in referring to any one of these seven steps they shall be referred to as test (A) through (G) as follows:

  1. Preliminary Test
  2. Sensor String Test
  3. Amplifier Test
  4. Regulated Vacuum Test
  5. System Vacuum Test
  6. Temperature Dial Test
  7. Intermittency Test

This procedure is designed to assist servicemen in locating a malfunction in the Automatic Climate Control system, when the system turns ON, but operates only in maximum heat or maximum air conditioner at high blower speed. If the system is operating incorrectly, but does have some degree of self-modulation, first check adjustment of temperature dial as described in step (F). If system still performs incorrectly, proceed as follows:

NOTE: For positive results, the Automatic Climate Control system should be tested in an area where the ambient temperature is between 70°F and 80°F. If the ambient temperature is below 70°F, the system may not produce full air conditioning, or if above 80°F, the system may not produce full heat.
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