B1100
Read the instructions below then 
start the fault diagnostic procedure.
Symptom: Car with single-speed radiator fan:
The radiator fan runs constantly (even when ignition OFF)
Battery runs flat.
Radiator fan not working, can lead to engine overheating.
Car with dual-speed radiator fan:
Radiator fan runs constantly at low speed (even when ignition OFF)
Battery runs flat.
Radiator fan only runs at high speed, which can lead to high motor temperature.
 
  
 
 
  
  
   
   
    
    
     
     
     Low Speed Radiator Fan Relay. Short to B+
    
    
     
     
     Low Speed Radiator Fan Relay. Open Circuit / Short to Ground
    
    
     
    
    
   
   
  
   Fault symptoms
  
  
   Car with single-speed radiator fan:
   
   
  
  
  
   
    
     
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       The radiator fan runs constantly (even when ignition OFF)
        
        
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       Radiator fan not working, can lead to engine overheating.
        
        
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   Car with dual-speed radiator fan:
   
   
  
  
  
   
    
     
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       •
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       Radiator fan runs constantly at low speed (even when ignition OFF)
        
        
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       Radiator fan only runs at high speed, which can lead to high motor temperature.
        
        
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   Conditions
  
  
   The control module output is monitored. If there is a short to ground/B+ or an open circuit in the relay circuit, a DTC is generated.
   
   
   
    Diagnostic help
   
  
  
   The output from the control module can be activated using the diagnostic tool.