sensor AUDI A4 2000 B5 / 1.G AEB Engine Technical Data Spark Plug
Page 2 of 22
28-2
      
Camshaft Position (CMP) sensor -G40-, 
checking
 
     
Required special tools and test equipment  
     
VAG 1598/22 test box 
     Multimeter US 1119 (Fluke 83 or equivalent) 
     VW 1594 connector test kit 
     Wiring diagrams 
     
Checking  
     
-  Disconnect 3-pin connector from Camshaft 
Position -G40- sensor. 
    
-  Connect multimeter US 1119 (Fluke 83 or equivalent) to measure 
voltage across CMP connector terminals 1 (B+) and 3 (Ground), using 
adapter cables from VW 1594 connector test kit. 
-  Switch ignition on.
-  Measure voltage between terminals 1 and 3. 
   Specified value: 4.5 volts minimum
-  Switch ignition off.
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Page 4 of 22
28-4
       If wiring is OK (and voltage across terminals 1 
and 3 is OK):  
     
-  Replace Camshaft Position (CMP) sensor.
      If wiring is OK (but still no voltage across 
terminals 1 and 3 :  
     
-  Replace Motronic ECM -J220-   Page 01
-57
 .
     
-  Carry out adaptation of throttle valve control 
module to ECM   Page 24
-119
 . 
     
- Check readiness code   Page 01
-59
 . If 
Diagnostic Trouble Code (DTC) memory has 
been erased, or ECM was disconnected, 
generate new readiness code   Page 01
-62
 . 
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Page 5 of 22
28-5
      
Knock sensor and knock sensor 
system, checking
 
     
Required special tools and test equipment  
     
VAG 1551/1552 Scan Tool (ST) with adapter 
cable VAG 1551/3 
     VAG 1598/22 test box 
     Multimeter US 1119 (Fluke 83 or equivalent) 
     VW 1594 connector test kit 
     Wiring diagrams 
     
Checking  
     
-  Connect VAG 1551/1552 Scan Tool (ST) and 
press buttons -0- and -1- to insert "Engine 
Electronics" address word 01 (engine running at 
idle)  Page 01
-7 . 
Rapid data transfer 
HELP
Select function XX
    
Indicated on display  
-  Press buttons -0- and -8- to select "Read Measuring Value Block" 
function 08, and press -Q- button to confirm input. 
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Page 7 of 22
28-6
 
Read Measuring Value Block 20 1 2 3 4 
    
Indicated on display (1-4   display groups)  
Note:  
The test must be carried out during a road test because the knock sensor 
system is only active as of a certain engine speed. 
WARNING! 
A second technician is required to operate the VAG 1551 scan tool 
during the road test. -  Road test car and compare display with specified values for knock 
sensor system in display field 1-4. 
  
Display groups  
  
1   2   3   4  
Display group 20: Knock sensor system  
Display  
xx.x   
xx.x   
xx.x   
xx.x   
Indicates   Timing correction,   
cylinder 1  Timing correction,  
cylinder 2  Timing correction  
cylinder 3  Timing correction,  
cylinder 4  
Range  
0.0 -15.0   
(crankshaft)  
0.0 -15.0   
(crankshaft)  
0.0 -15.0   
(crankshaft)  
0.0 -15.0   
(crankshaft)  
Specified value  
0.0 -10.0   
(crankshaft)  
0.0 -10.0   
(crankshaft)  
0.0 -10.0   
(crankshaft)  
0.0 -10.0   
(crankshaft)  
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Page 9 of 22
28-7
       If displayed values are OK:  
     
- Check readiness code   Page 01
-59
 . If 
Diagnostic Trouble Code (DTC) memory has 
been erased, or ECM was disconnected, 
generate new readiness code   Page 01
-62
 . 
     
- 
Press   button to advance program 
sequence.      
-  Press buttons -0- and -6- to select "End Output" 
function 06, and press -Q- button to confirm 
input. 
Evaluating display group 20  Display group: 20  
Display fields: 1-4  
Possible cause  
  
Correcting action  
  
All cylinders retarded more 
than 10  (crankshaft)  
Knock sensor faulty- Continuation   Page 28
-8
  
Connector corroded  
  Knock sensor 
incorrectly torqued - Loosen knock sensor and re-tighten to 20 Nm (15 ft lb)
  Components loose 
on engine - Tighten components
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Page 11 of 22
28-8
      
Continuation  
     
-  Disconnect 3-pin connector from Knock Sensor 
(KS) 1 -G61-. 
    
If resistance is OK (no continuity):  -  Connect multimeter US 1119 (Fluke 83 or equivalent) to measure 
resistance between connector terminals, using adapter cables from VW 
1594 connector test kit. 
 
Connector terminal 1 to terminal 2
 Connector terminal 1 to terminal 3
 Connector terminal 2 to terminal 3
 Specified value:   
-  Connect VAG 1598/22 test box to Motronic ECM harness connector   
Page 01
-56
 . 
    
-  Check wiring for open circuit between ECM/test box and 3-pin harness 
connector, according to wiring diagram. 
 
Connector terminal 1 to ECM/test box socket 68
 Connector terminal 2 to ECM/test box socket 67
 Connector terminal 3 to ECM/test box socket 2
 Specified value: max. 1.5 
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Page 12 of 22
28-9
      
-  Check wiring for short circuits between terminals 
of 3-pin connector, and between connector and 
ECM/test box. 
     
 
Connector terminal 2 to ECM/test box 
socket 68 
     
 Connector terminal 3 to ECM/test box 
socket 68 
     
 Connector terminal 3 to ECM/test box 
socket 67 
     
 Specified value: 
      If the wiring is OK:  
     
-  Loosen knock sensor and re-tighten to 20 Nm 
(15 ft lb). 
      If the malfunction still exists (stored in DTC 
memory):  
     
-  Replace Knock Sensor (KS) 1 -G61-.
     
- 
Check readiness code   Page 01
-59
 . If 
Diagnostic Trouble Code (DTC) memory has 
been erased, or ECM was disconnected, 
Pa
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Page 14 of 22
28-10
      
-  Disconnect 3-pin connector from Knock Sensor 
(KS) 2 -G66-. 
    
If resistance is OK (no continuity):  -  Connect multimeter US 1119 (Fluke 83 or equivalent) to measure 
resistance between connector terminals, using adapter cables from VW 
1594 connector test kit. 
 
Connector terminal 1 to terminal 2
 Connector terminal 1 to terminal 3
 Connector terminal 2 to terminal 3
 Specified value:   
-  Connect VAG 1598/22 test box to Motronic ECM harness connector   
Page 01
-56
 . 
    
-  Check wiring for open circuit between ECM/test box and 3-pin harness 
connector, according to wiring diagram. 
 
Connector terminal 1 to ECM/test box socket 60
 Connector terminal 2 to ECM/test box socket 67
 Connector terminal 3 to ECM/test box socket 2
 Specified value: max. 1.5 
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Page 15 of 22
28-11
      
-  Check wiring for short circuits between terminals 
of 3-pin connector, and between connector and 
ECM/test box. 
     
 
Connector terminal 2 to ECM/test box 
socket 60 
     
 Connector terminal 3 to ECM/test box 
socket 60 
     
 Connector terminal 3 to ECM/test box 
socket 67 
     
 Specified value: 
      If the wiring is OK:  
     
-  Loosen knock sensor and re-tighten to 20 Nm 
(15 ft lb). 
      If the malfunction still exists (stored in DTC 
memory):  
     
-  Replace Knock Sensor (KS) 2 -G66-. 
     
- 
Check readiness code   Page 01
-59
 . If 
Diagnostic Trouble Code (DTC) memory has 
been erased, or ECM was disconnected, 
Pa
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