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System Functional Test

  1. Measure and record height of rear fender opening. Discharge system completely at compressor bleed valve. Place 400 lb. load in trunk or on tailgate. Again measure and record height of rear fender opening. Start and idle engine. Feel compressor to determine if it is operating; if not, check rubber vacuum line for blockage or improper connections. If compressor is still inoperative, replace it. If unit is operating, let it run for 10-15 minutes until compressor stops.
  2. Measure and record height of rear fender opening. Difference between this measurement and measurement after placing weight on vehicle should be 3/4" minimum. If less than 3/4", accelerate-decelerate engine to determine if measurement changes. Remove load from vehicle. After two minutes, measure and record height of rear fender opening. Difference between this measurement and original measurement must not be greater than 1/4".
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