P1760
Symptom: "CHECK ACS" warning lamp on. If engine load is absent, a minor decrease in comfort will result.
 
  
 
 
  
  
   
   
    
     Engine load, signal wrong
    
    
     Fault symptom
    
   
   
    "CHECK ACS" warning lamp on. If engine load is absent, a minor decrease in comfort will result.
    
    
    
     Condition
    
   
   
    Engine load is a PWM signal from the TRIONIC system. The frequency is proportional to engine rpm. The input signal is absent or faulty.
    
    
    
     Diagnostic procedure
    
    
     1 Check the engine load signal
    
    
      
    
    
   
   
  
  
   
    
     
      | - | Connect the Scan tool diagnostics instrument to the car's data link connector. 
 
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      | - | Select the "ENGINE LOAD" command in the "READ FUNCTIONS" menu. The nominal value at idling speed is about 0%%. 
 
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      | - | Open the throttle and note whether the value increases considerably. 
 
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   Is functionality OK?
  
  
  
   
    Continue with point 2.
    
    
   
  
  
  
  
   
    Repair or replace the lead in question and proceed to point 2.
    
    
   
  
  
  
   2 Final check
  
  
    
  
  
  
  
   
    
     
      | - | Clear the diagnostic trouble code. 
 
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      | - | Perform a drive cycle by driving the car at varying engine rpm and loads for 5 minutes. 
 
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      | - | Check whether the diagnostic trouble code has recurred. 
 
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   Has the diagnostic trouble code recurred?
  
  
  
   
    Continue as described in the section "Before replacing a control module", see
    
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    The steps taken to rectify the fault were correct.