24-152
      
Continuation  
      If no speed was indicated:  
    
Notes: 
If the LED does not blink:  
 Electrical Wiring Diagrams, Troubleshooting & Component Locations   
If the wiring is OK and the LED does not blink:  
 Repair Manual, Electrical Equipment, Repair Group 90
    -  Connect VAG 1598/22 test box to ECM harness connector   Page 01
-
56
 . 
-  Connect VAG 1527B LED voltage tester between ECM/test box 
sockets 3 (B+) and 20 (signal). 
-  Lift vehicle at left front until wheel is free.
-  Switch ignition on and rotate left-front wheel by hand.
   LED must blink (very brief blink)
The right-front wheel must not rotate; block it if necessary.For LEDs with little voltage consumption, the LED lights up at half 
strength when the ignition is switched on. 
-  Check wiring from ECM connector, terminal 20 to instrument cluster for 
open circuit or short circuit 
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        24-161
      
Rough road signal from ABS/EDL 
control module, checking
 
     
Notes:  
     
When the ABS/EDL control module senses a 
wheel spinning, it produces the rough road 
signal. When the ECM recognizes the rough 
road signal, the misfire recognition is switched 
off. 
     Check the rough road signal only when the 
trouble code 18014 "Rough Road Spec Engine 
Torque ABS-ECU Electrical Malfunction" is 
stored. The "Misfire" malfunction is in this case 
a subsequent malfunction that can be 
disregarded. 
     The wiring and the rough road signal are 
monitored by the ECM. 
     Emissions testing on a front-wheel drive vehicle 
with ABS/EDL, during which only the front 
wheels turn while the rear wheels are 
stationary, can result in the DTC 18014 being 
stored in DTC memory. Therefore, the fuse for 
the ABS/EDL control module must be removed. 
After the test, check DTC memory for the 
ABS/EDL control module and the ECM. Then 
erase DTC memory. 
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