Refrigerant System Tests

NOTE: In order to perform an accurate test the vehicle ambient temperature must be 21°C (70°F) or above.

1. NOTE: Procedure 1 — Ambient Temperature between 21°C (70°F) and 38°C (100°F)

   Run the engine until it reaches normal operating temperature.
   

1. Connect the air conditioning service unit to the refrigerant system.
   

1. Set temperature to (lowest possible temp setting) with the dual function disabled (if equipped). Manually set blower on HI. If the vehicle has a fresh air/recirc button, set it to FRESH. If the vehicle has an Air Conditioning (A/C) switch or compressor on switch, set it to Air Conditioning (A/C) ON.
   

1. Open all vehicle windows and leave the hood open for the test. Open the rear doors.
   

1. Confirm the compressor is operating and the engine cooling fan(s) are operating or engaged. Allow the vehicle to idle until the suction (low-side) and discharge (high-side) pressures are stable or fluctuate in a range that repeats.
   

1. Record the ambient (shop) temperature.
   

1. Record the discharge pressure. If the pressure is fluctuating, record the average value.
   

1. Determine if the discharge pressure falls within the normal operating limits using the Normal Refrigerant Discharge Pressures 21 - 38°C (70 - 100°F) Ambient (30 - 60% Relative Humidity) chart below.
   

1. Record the suction pressure. If the pressure is fluctuating, record the average value.
   

1. Determine if the suction pressure falls within the normal operating limits using the Normal Refrigerant Suction Pressures 21 - 38°C (70 - 100°F) Ambient (30 - 60% Relative Humidity) chart below.
   

1. Proceed to the Refrigerant System Tests Diagnostic Table.
   Refer to: Climate Control System - Vehicles With: Dual Automatic Temperature Control (DATC) (412-00 Climate Control System - General Information, Diagnosis and Testing).
   Refer to: Climate Control System - Vehicles With: Electronic Manual Temperature Control (EMTC) (412-00 Climate Control System - General Information, Diagnosis and Testing).
   

1. NOTE: Procedure 2 — Ambient Temperature Above 38°C (100°F)

   Run the engine until it reaches normal operating temperature.
   

1. Connect the air conditioning service unit to the refrigerant system.
   

1. Set temperature to (lowest possible temp setting) with the dual function disabled (if equipped). Manually set blower on HI. If the vehicle has a fresh air/recirc button, set it to FRESH. If the vehicle has an Air Conditioning (A/C) switch or compressor on switch, set it to Air Conditioning (A/C) ON.
   

1. Open all vehicle windows and leave the hood open for the test. Open the rear hatch and/or rear doors (if equipped).
   

1. Confirm the compressor is operating and the engine cooling fan(s) are operating or engaged. Allow the vehicle to idle until the suction (low-side) and discharge (high-side) pressures are stable or fluctuate in a range that repeats.
   

1. Record the ambient (shop) temperature.
   

1. Record the discharge pressure. If the pressure is fluctuating, record the average value.
   

1. Determine if the discharge pressure falls within the normal operating limits using the Normal Refrigerant Discharge Pressures 38 - 49°C (100 - 120°F) Ambient (15 - 40% Relative Humidity) chart below.
   

1. Record the suction pressure. If the pressure is fluctuating, record the average value.
   

1. Determine if the suction pressure falls within the normal operating limits using the Normal Refrigerant Suction Pressures 38 - 49°C (100 - 120°F) Ambient (15 - 40% Relative Humidity) chart below.
   

1. Proceed to the Refrigerant System Tests Diagnostic Table.
   Refer to: Climate Control System - Vehicles With: Dual Automatic Temperature Control (DATC) (412-00 Climate Control System - General Information, Diagnosis and Testing).
   Refer to: Climate Control System - Vehicles With: Electronic Manual Temperature Control (EMTC) (412-00 Climate Control System - General Information, Diagnosis and Testing).
   

Copyright © Ford Motor Company