A/C blows warm — no cold air
A/C system runs but vents blow ambient or warm air on max cold.
R107 A/C is pushbutton ACC (automatic climate control). Original R12 systems are often retrofitted to R134a. Compressor must engage; refrigerant must be charged correctly.
What the diagnosis checks
- Does the A/C compressor clutch engage (audible click, hub spinning)?
- Manifold gauge low side ~25–45 psi, high side ~150–250 psi at idle?
- 12 V at the compressor clutch coil with A/C on?
Possible causes it points to
- Climate blend flap stuck on heat
- Refrigerant charge wrong
- Compressor clutch coil
- Low-pressure switch / no charge
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