HVAC A/C Clutch Relay Control Circuit
What does B1206 mean?
The B1206 code means the vehicle's onboard diagnostic system has detected: HVAC A/C Clutch Relay Control Circuit. This is a moderate severity code.
Common Symptoms
- A/C compressor not engaging
- No cold air from vents
- A/C clutch cycling rapidly
- A/C works intermittently
- Clicking sound from A/C relay area
Probable Causes (Ranked by Likelihood)
- Faulty A/C clutch relay Very High
- Defective A/C compressor clutch coil High
- Low refrigerant triggering pressure switch cutoff Moderate
- Damaged wiring to A/C clutch relay Moderate
- HVAC or PCM not commanding relay on Low
Step-by-Step Diagnostic Procedure
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Check A/C clutch relay by swapping with identical relay
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Test A/C compressor clutch coil resistance
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Check refrigerant pressure with manifold gauges
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Verify relay control signal from BCM or PCM
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Inspect wiring from relay to A/C compressor clutch
Frequently Asked Questions
Can I swap relays to test if the A/C relay is bad?
Yes. Most fuse boxes have identical relays for different circuits. You can swap the A/C relay with another same-type relay to see if the A/C starts working.
Why does low refrigerant affect the relay circuit?
The A/C system has a pressure switch that prevents the compressor from running with low refrigerant to avoid damage. This can trigger codes related to the clutch relay circuit.
How much does an A/C relay cost?
An A/C relay typically costs $10-$30 for the part and is easy to replace by simply pulling out the old relay and plugging in the new one.