Relay unit, radiator fans (706a), Z19
 
  
 
 
  
   
    
     |  | Relay unit, radiator fans (706a), Z19 | 
   
  
  
  
   Relay unit containing relays and resistors and thermal fuse.
   
   
   
   
   
   
   
  
  
   
   
    
     
     
     
    
    
     
      | Pin No. | Signal type | Description | 
     
      | 3 | +30 | Power supply 37RH from fuse holder 748. | 
     
      | 6 | +30 | Power supply 37LH from fuse holder 748. | 
     
      | 2 | Power ground | Grounding of 37LH in grounding point G2. | 
     
      | 5 | Power ground | Grounding of 37RH in grounding point G2. | 
     
      | 1, 4 and 7 | Control. Ground= active | Grounded by the ECM. The pins are grounded differently depending on current fan stage, see table below. | 
    
   
   
   
  
  
   
   
   
    Connection stage
   
   
    
     
     
     
     
    
    
     
      | Stage | Pin 7 | Pin 4 | Pin 1 | 
     
      | 1 | grounded |  |  | 
     
      | 2 |  | grounded |  | 
     
      | 3 | grounded | grounded |  | 
     
      | 4 | grounded | grounded | grounded | 
    
   
   
   
  
  
   In stage 1 the fan motors are connected in series and supplied with voltage via pin 6.
   
   
  
  
  
   
    
     
      | • | Power supply 
 
   
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      | • | Control 
 
   
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