HVAC Blower Motor Control Circuit Malfunction
What does B1200 mean?
The B1200 code means the vehicle's onboard diagnostic system has detected: HVAC Blower Motor Control Circuit Malfunction. This is a moderate severity code.
Common Symptoms
- Blower motor not working on any speed
- No air flow from vents
- Blower only works on high speed
- Intermittent blower operation
- Burning smell from vents when blower runs
Probable Causes (Ranked by Likelihood)
- Failed blower motor resistor or control module Very High
- Defective blower motor High
- Corroded blower motor connector Moderate
- Blown blower motor fuse or relay Moderate
- HVAC control head malfunction Low
Step-by-Step Diagnostic Procedure
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Check blower motor fuse and relay
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Test voltage at blower motor connector
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Inspect blower motor resistor or control module
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Check blower motor connector for corrosion
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Test blower motor by applying direct power
Frequently Asked Questions
Why does my blower only work on high?
This is a classic symptom of a failed blower motor resistor. The resistor controls lower speeds, but high speed bypasses the resistor, so it still works.
Is it safe to drive without the blower working?
Yes, the vehicle is safe to drive, but you will not have defrost capability, which is a safety concern in cold or humid weather.
Where is the blower motor resistor?
The blower motor resistor is typically located near the blower motor, under the passenger side dashboard. It is accessible by removing a small panel in many vehicles.