GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1998 🢒 Tracker - 4WD 🢒 HVAC 🢒 HVAC Systems - Manual 🢒 HVAC System Check

Step

Action

Normal Result(s)

Abnormal Result(s)*

1
    • Start the engine.
    • Move the blower speed selector switch from OFF to the following positions in the following order:
        1. LOW
        2. MEDIUM 1
        3. MEDIUM 2
        4. HIGH
        5. OFF
    • The blower motor speed increases as the blower speed selector switch is moved towards the HIGH position.
    • The blower motor speed decreases as the blower speed selector switch is moved towards the LOW position.

2
    • Engine idling until operating temperature is reached.
    • Move the mode control to the heat mode.
    • Move the temperature control to full heat.
    • Heated air is delivered to the passenger compartment.
    • Most of the heated air is delivered through the floor outlets with some air delivered to the windshield and side window outlets.
    • Heating Insufficient
    • Heat Excessive (Heater Mode)
    • Air Delivery Improper
    • Heat Excessive (Vent Mode)
    •  Noise Diagnosis
    • High or Low Temperature Control Effort

3
    • Engine still idling.
    • Move the mode control to the defrost mode.
    • Move the temperature control to full heat.
    • Heated air is delivered to the passenger compartment.
    • Most of the heated air is delivered to the windshield with some air delivered to the side window outlets.
    • Defrosting Insufficient
    • Heat Excessive (Heater Mode)
    • Air Delivery Improper
    • Heat Excessive (Vent Mode)
    •  Noise Diagnosis
    • High or Low Temperature Control Effort

4
    • Engine still idling.
    • Move the blower speed selector switch to any position except OFF.
    • Move the temperature control to the full cold position.
    • Press the A/C switch to ON.
    • The blower motor runs.
    • The condenser fan motor runs.
    • The A/C compressor clutch engages.
    • Cold air is delivered to the passenger compartment.
    • The compressor stops running if the engine coolant temperature exceeds 113°C (235°F).
    • The compressor and the condenser fan motor stop running if any of the following conditions are met:
      • The A/C system pressure drops below 193 kPa (28 psi)
      • The A/C system pressure exceeds 3137 kPa (455 psi)
      • The evaporator core temperature drops below 0°C (32°F)
    •  Odor Diagnosis
    •  Noise Diagnosis

5
    • Press the A/C switch to OFF.
    • Move the blower speed selector switch to OFF.
    • The blower motor stops.
    • The A/C compressor clutch disengages.
    • The condenser fan motor stops once the engine coolant temperature drops below 113°C (235°F).
    •  Blower Motor Always On

* Refer to the appropriate symptom diagnostic table for the applicable abnormal result.