LEMON Manuals: Even more car manuals for everyone
Home >> GMC >> 2003 >> Safari Van Cargo, AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 23 (HVAC Systems - Manual) >> System Tests >> A/C Pressure Zone "B" Diagnosis

A/C Pressure Zone "B" Diagnosis

WARNING: This page is about a different car, the 2002 GMC Safari and 2002 Chevrolet Astro. However, it is still accessible from the selected car via links, so may be relevant.
WARNING: Avoid contact with moving parts and hot surfaces while working around a running engine in order to prevent physical injury.
NOTE: Definition: The low side pressure is higher than normal and the high side pressure is lower than normal.
  1. Were you sent here from the A/C System Performance Test? If so, go to next step. If not, see A/C PERFORMANCE TEST .
  2. After continued operation of the A/C system, do the low and high side pressures equalize or become static? If so, go to step  5. If not, go to next step.
  3. Refer to the pressures recorded during the A/C system performance test. See A/C PERFORMANCE TEST . Inspect for the following conditions: The low side pressure equal to or above the specified pressure range of the A/C performance table. The high side pressure is below the specified pressure range of the A/C performance table. See Figure-Figure . The low side refrigerant line at the compressor feels cool-to-warm. The high side refrigerant line at the compressor feels warm-to-hot. Do any of the listed conditions exist? If so, go to step  5. If not, go to next step.
  4. Refer to the pressures recorded during the A/C system performance test. See A/C PERFORMANCE TEST . Inspect for the following conditions: The low side pressure is above the specified pressure range of the A/C performance table. See Figure-Figure . The high side pressure is below the specified pressure range of the A/C performance table. The low side refrigerant line at the compressor feels warm. The high side refrigerant line at the compressor feels warm-to-hot. Do the listed conditions exist? If so, go to next step. If not, perform the A/C PERFORMANCE TEST .
  5. The A/C system has a low refrigerant charge. Evacuate and recharge the A/C system. See RECOVERY EVACUATING & RECHARGING in GENERAL SERVICING PROCEDURES article in GENERAL SERVICING. After repairs, go to next step.
  6. After you perform the repairs, record the following: The low and high side pressures and A/C outlet air temperature. Compare the pressures and the temperature to those listed in the A/C performance chart. See Figure-Figure . Are the readings within the specified ranges found on the A/C performance chart? If so, go to step  13.
  7. The A/C compressor is malfunctioning. Remove the orifice tube and inspect for contamination. See ORIFICE TUBE  under REMOVAL & INSTALLATION. Are there metal flakes on the orifice tube? If so, step  9. If not, go to next step.
  8. Inspect the orifice tube for a Brown, powdery residue indicating desiccant in the A/C system. Is there a Brown, powdery residue present? If so, go to step  11. If not, go to step  12.
  9. Remove the compressor hose from the compressor. See COMPRESSOR HOSE ASSEMBLY  under REMOVAL & INSTALLATION. Inspect for metal flake contamination at the line connections and the compressor ports. Is there metal flake contamination present? If so, go to next step. If not, go to step  12.
  10. Replace the A/C compressor. See COMPRESSOR  under REMOVAL & INSTALLATION. Install an A/C refrigerant filter. See REFRIGERANT FILTER INSTALLATION  under REMOVAL & INSTALLATION. Replace the orifice tube. See ORIFICE TUBE  under REMOVAL & INSTALLATION. Evacuate and recharge the A/C system. See RECOVERY EVACUATING & RECHARGING in GENERAL SERVICING PROCEDURES article in GENERAL SERVICING. After repairs are complete, go to step  13.
  11. Flush the A/C system. See FLUSHING PROCEDURES in GENERAL SERVICING PROCEDURES article in GENERAL SERVICING. Replace the orifice tube. See ORIFICE TUBE  under REMOVAL & INSTALLATION. Replace the A/C compressor. See COMPRESSOR  under REMOVAL & INSTALLATION. Replace the accumulator. See ACCUMULATOR  under REMOVAL & INSTALLATION. Evacuate and recharge the A/C system. See RECOVERY EVACUATING & RECHARGING in GENERAL SERVICING PROCEDURES article in GENERAL SERVICING. After repairs are complete, go to step  13.
  12. Replace the A/C compressor. See COMPRESSOR  under REMOVAL & INSTALLATION. Evacuate and recharge the A/C system. See RECOVERY EVACUATING & RECHARGING in GENERAL SERVICING PROCEDURES article in GENERAL SERVICING. After repairs, go to next step.
  13. Operate the system in order to verify the repair. Did you find and correct the condition? If so, system is okay. If not, go to step  2.
scientia non olet · About LEMON Manuals