AUDI A4 1997 B5 / 1.G AFC Engine Ignition Coil Power Output Stage Checking Workshop Manual
Page 1 of 3
28-13
 
     
Ignition coil power output 
stage, checking 
      Component locations   page 28
-1 .  
     
Fuse for ignition coils OK 
     Ignition coils OK; checking   page 28
-16
 
     
Checking voltage supply  
    
If the specified value is not obtained:  -  Disconnect 3-pin power output stage harness connector.
-  Switch Fluke 83 multimeter to voltage range and connect between 
Ground (GND) and terminals 1, 2 and 3 in sequence. 
-  Switch ignition on.
   Specified value: approx. battery voltage
-  Eliminate open circuit in wiring using wiring diagram.
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Page 2 of 3
28-14
      
Checking Ground (GND)  
     
-  Disconnect 4-pin power output stage harness 
connector. 
    
If the specified value is not obtained:  
Checking triggering   -  Switch Fluke 83 multimeter to voltage range, connect between 
connector terminal 2 (GND) and battery positive voltage (B+). 
   Specified value: approx. battery voltage
-  Eliminate open circuit using wiring diagram; repair as necessary.
    
-  Disconnect 4-pin power output stage harness connector.
-  Disconnect all six fuel injector harness connectors.
-  Connect voltage tester between Ground (GND) and connector 
terminals 1, 3 and 4 in sequence. 
-  Switch ignition on.
-  Operate starter for several seconds.
Voltage tester must flash 
Pa
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gnition coil 
power out
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11/23/2002 htt
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Page 3 of 3
28-15
       If voltage tester does not flash:  
     
-  Switch ignition off.
    
If wiring is OK:  
If voltage tester flashes, wiring is OK.  
If, during On Board Diagnostic, the diagnostic trouble codes 
P1393/17801, P1394/17802, or P1395/17803 ("Ignition Coil Power Output 
Stage 1/2/3 Electrical Malfunction") are displayed:  -  Switch Fluke 83 multimeter to resistance range and check wiring for 
continuity between power output stage harness connector and ECM 
harness connector. 
-  Connect VAG 1598/19 test box to ECM harness connector   page 01
-
255
 . 
-  Locate open circuit using wiring diagram; repair as necessary.
Power output stage terminal 
number  ECM connector B terminal 
number  
1   B7  
3   B6  
4   B5  
- Replace ECM   page 01
-265
 .
-  Replace ignition coil power output stage.
Pa
ge 3 of 3 I
gnition coil 
power out
put sta
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g
11/23/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.28.3