P0647
Book Code P0647 Inspection
Automotive Climate Control
Low / Normal Under Shade
Code P0647 - A/C Clutch Relay Control Circuit High
Indicates an open circuit or short-to-voltage condition in the A/C clutch relay control circuit.
Safe to Drive? ✅ Yes, Safe
Estimated Repair Cost 60 - 250 SAR
Common Makes Generic, Ford, GM, Chrysler, Jeep
System Category relay
Symptoms of Trouble Code P0647:
- ⚠️ Compressor remains engaged even after AC button is switched off
- ⚠️ Thick ice formation on underhood low-pressure aluminum lines
- ⚠️ Warm vent air if relay is open circuit
Common Causes Behind Code P0647:
- 🔍 Relay internal switch contacts fused/welded closed
- 🔍 Broken PCM control circuit wire
- 🔍 Faulty magnetic clutch coil
Diagnostic Procedure Recommended by Auto Save Technicians:
- 1 Pull AC relay to check if compressor immediately disengages
- 2 Replace with a brand new OEM relay
Specialist Recommendation:
Request Parts & Repair Quote
If compressor runs with AC switch off, pull relay immediately to prevent pipe freeze-up.
Associated Components: AC Relay Clutch Assembly
Frequently Asked Questions: Code P0647
What is the danger of a compressor that never cycles off?
It freezes the evaporator core, completely chokes cabin airflow, wastes fuel, and strains the engine belt.