Testing for Short to Ground
 
  
 
 
  
   
    
     |  | Testing for Short to Ground | 
   
  
  
   
   
    
    
    
    
    
   
   
    
   
   
    Refer to
    
     Test Probe Caution
    
    
    
   
   
    The following procedures test for a short to ground in a circuit.
    
    
    
    
    
    
    
     
      
       | With a Digital Multimeter (DMM) | 
     
    
   
   
    
   
   
   
    
     
      
       | 1. | Remove the power feed (i.e. fuse, control module) from the suspect circuit. 
 
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       | 3. | Set the rotary dial of the DMM to the Ω position. 
 
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       | 4. | Connect one lead of the DMM to one end of the circuit to be tested. 
 
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       | 5. | Connect the other lead of the DMM to a good ground. 
 
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       | 6. | If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit. 
 
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       | 1. | Remove the power feed (i.e. fuse, control module) from the suspect circuit. 
 
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       | 3. | Connect one lead of the test lamp to battery positive voltage. 
 
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       | 4. | Connect the other lead of the test lamp to one end of the circuit to be tested. 
 
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       | 5. | If the test lamp illuminates, there is a short to ground in the circuit. 
 
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      | Fuse Powering Several Loads | 
    
   
   
    
   
   
   
    
     
      
       | 1. | Review the system schematic and locate the fuse that is open. 
 
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       | 2. | Open the first connector or switch leading from the fuse to each load. 
 
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       | 3. | Connect a DMM across the fuse terminals (be sure that the fuse is powered). 
 
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       |  | • | When the DMM displays voltage the short is in the wiring leading to the first connector or switch. 
 
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       |  | • | If the DMM does not display voltage refer to the next step. 
 
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       | 4. | Close each connector or switch until the DMM displays voltage in order to find which circuit is shorted. 
 
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