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GMC Sierra T1XX (2019-Present) AC not blowing cold air, how to fix it - GMC Sierra
Home/Cars/GMC/Sierra/T1XX (2019-Present)/GMC Sierra T1XX (2019-Present) AC not blowing cold air, how to fix it

GMC Sierra T1XX (2019-Present) AC not blowing cold air, how to fix it

GMC Sierra T1XX (2019-Present)

Error Codes
2-4 hours
Time
medium
Difficulty
medium
Severity
Navigation
ProblemSymptomsDiagnosisSolution
ProblemSymptomsDiagnosisSolution
3 min read
575 words

Problem Statement

Learn how to diagnose and fix AC not blowing cold air in GMC Sierra T1XX. Step-by-step guide with symptoms, diagnostic steps, and repair instructions.

Affected Component
HVAC
Estimated Time
2-4 hours

⚠️ Safety Warnings

Important safety information - read before proceeding

  • •Disconnect the battery before working on the electrical components of the AC system.
  • •Allow the engine and AC components to cool before beginning repairs to avoid burns.

Symptoms

  • •AC system blowing warm air
  • •Unusual noises when the AC is activated
  • •AC compressor not engaging
  • •Ice buildup on the evaporator
  • •AC warning light illuminated on the dashboard

Diagnostic Steps

  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  6. 6

Solution

💡 Expert Tip

For complex repairs like this, consider taking photos at each step. This helps if you need to reverse a step or consult with a mechanic. Also, keep all removed parts organized - you may need to reference them during reassembly.

Verification

After completing the repair, verify that the issue has been resolved:

  • ✓Test the affected component to ensure it functions correctly
  • ✓Check for any error codes or warning lights
  • ✓Monitor the vehicle for a few days to ensure the issue does not recur

Prevention Tips

To prevent this issue from occurring again:

  • •Follow the manufacturer's recommended maintenance schedule
  • •Address warning signs early before they develop into major issues
  • •Use quality parts and fluids recommended for your vehicle
  • •Keep detailed records of all repairs and maintenance

Tools & Equipment Required

  • •OBD-II scanner
  • •Manifold gauge set
  • •Multimeter
  • •Socket set
  • •Screwdriver set
  • •Safety glasses and gloves

Parts Required

  • •Refrigerant (R-134a or R-1234yf, as specified)
  • •AC compressor (if needed)
  • •Cabin air filter

Additional Information

Affected Component
HVAC
Estimated Time
2-4 hours
Difficulty
medium
Severity
medium
Tools Required
6 items
Parts Required
3 items

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Solution
1. Preparation
  • Gather tools and parts required for the repair.
  • Ensure the vehicle is parked on a level surface and the engine is off.
  • Disconnect the battery to prevent electrical shock.

Tools Required:

  • OBD-II scanner
  • Manifold gauge set
  • Multimeter
  • Socket set
  • Screwdriver set
  • Safety glasses and gloves
2. Recharge Refrigerant
  1. Check Refrigerant Level:

    • Connect the low-pressure side of the manifold gauge set to the AC service port.
    • Read the pressure on the gauge; if it's below the manufacturer's specifications, proceed to the next step.
  2. Add Refrigerant:

    • Attach the refrigerant canister to the manifold gauge set.
    • Open the valve and add refrigerant slowly while monitoring the gauges to avoid overfilling.
    • Follow the manufacturer's specifications for the correct type and amount of refrigerant.
3. Repair or Replace Components
  1. AC Compressor:

    • If the compressor clutch does not engage, check the electrical connections using a multimeter.
    • If faulty, remove the AC compressor (disconnect lines, unbolt, and remove) and replace it with a new unit.
    • Reinstall and recharge the system.
  2. Fix Leaks:

    • If a leak is detected, use UV dye to pinpoint the source.
    • Replace any damaged hoses, seals, or components as necessary.
  3. Replace Cabin Air Filter:

    • Locate the cabin air filter access panel (typically under the glove compartment).
    • Remove the old filter and install a new one, ensuring it is seated properly.