Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Symptom Tests: Notes
Before testing system, visually inspect easily accessible system components for damage or defects. Inspect wiring harness and connections for damage and poor connections. Check aftermarket devices which could affect system operation. Verify that compressor clutch turns freely and is not seized.
Refer to symptom and perform corresponding test to diagnose problem. See SYMPTOM TEST DIRECTORY table.
| Symptom | See Test |
|---|---|
| Air Delivery Improper | A |
| Air Delivery Improper - Cargo Van with Auxiliary HVAC | B |
| Air Delivery Improper - Passenger Van with Auxiliary HVAC | C |
| Blower Motor Always On | D |
| Blower Motor Inoperative | E |
| Blower Motor Malfunction | F |
| Blower Motor Always On - with Auxiliary Heater Only or Cargo Van with Auxiliary HVAC | G |
| Blower Motor Always On - Passenger Van with Auxiliary HVAC | H |
| Blower Motor Inoperative - Auxiliary | I |
| Blower Motor Malfunction - Auxiliary | J |
| Compressor Clutch Does Not Disengage | K |
| Compressor Clutch Does Not Engage - 6.5L Engine | L |
| Compressor Clutch Does Not Engage - Except 6.5L Engine | M |
| Defrosting Insufficient | N |
| Too Cold In Vehicle | O |
| Too Cold In Vehicle - Cargo Van with Auxiliary HVAC | P |
| Too Cold In Vehicle - Cargo Van with Auxiliary Heater | Q |
| Too Cold In Vehicle - Passenger Van with Auxiliary HVAC | R |
| Too Hot In Vehicle | S |
| Too Hot In Vehicle - Cargo Van with Auxiliary HVAC | T |
| Too Hot In Vehicle - Cargo Van with Auxiliary Heater | U |
| Too Hot In Vehicle - Passenger Van with Auxiliary HVAC | V |
NO RELATED
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.