Procedure No. 2: Over 100°F (38°C)
- Drive vehicle or run engine until it reaches normal operating temperature. Connect a manifold gauge set or refrigerant service center with high-pressure and low-pressure gauges to refrigerant system.
- Set A/C controls for normal A/C-PANEL mode, full COOL temperature, FRESH air, MED LO blower. If vehicle has a fresh AIR/RECIRC button, set it to FRESH. If vehicle has an A/C switch or compressor on switch, set it to A/C ON. If vehicle is equipped with auxiliary climate control, set auxiliary controls to full COOL in PANEL mode at MED LO blower speed.
- Open all vehicle windows and leave hood open for test. Open rear hatch and/or rear doors (if equipped). Confirm compressor clutch is engaged and engine cooling fan(s) are operating or engaged. Allow vehicle to idle until suction (low-side) and discharge (high-side) pressures are stable or fluctuate in a range that repeats.
- Record ambient (shop) temperature. Record discharge pressure. If pressure is fluctuating, record average value. Determine if discharge pressure falls within normal operating limits using normal refrigerant discharge pressures chart. See Fig 1.
- Record suction pressure. If pressure is fluctuating, record average value. Determine if suction pressure falls between normal operating limits using normal refrigerant suction pressures chart. See Fig 2.
- Proceed to diagnostic table. See Figure.
Courtesy of FORD MOTOR CO.
Courtesy of FORD MOTOR CO.
