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Speedometer And Tachometer, Troubleshooting

Speedometer does not work

                                           
Vehicles with trip computer
Check average vehicle speed display as follows: -- Start engine-- Select average vehicle speed display (ø km/h or ø MPH) with trip computer function selector switch-- Drive vehicle-- While driving vehicle, push trip computer RESET button for at least 2 seconds, then release
  • Instantaneous vehicle speed is displayed
Yes   No  
                                           
  Speedometer faulty                 Vehicles without trip computer
  -- Replace speedometer SPEEDOMETER                   
                                           
                                           
        End                   Go to next article  
                                           
                                           
-- Remove instrument cluster INSTRUMENT CLUSTER -- Remove red and green 26-point connectors from instrument cluster-- Check connectors for bent terminals, repair as necessary-- Connect adapter harness : VAG1598/4  to red 26-point instrument cluster connector-- Connect adapter harness to instrument cluster and VAG 1598 test box-- Reconnect green 26-point connector to instrument cluster-- Set digital multimeter (Fluke 83 or equivalent) to AC (alternating current) volt range-- Connect multimeter between sockets 8 and 14 of VAG 1598 test box-- Place transmission in neutral and apply parking brake-- Raise vehicle on hoist-- Switch ignition ON and slowly rotate wheel
  • Voltage must vary between 1.0-4.5 V (vehicle speed signal from speedometer present)
Yes   No  
                                           
      Go to A           Vehicle speed signal not present
                        -- Check for open circuit in wiring to Speedometer Vehicle Speed Sensor (VSS) according to wiring diagram, repair as necessary, or-- Replace Speedometer VSS
                                           
                                End        
                                           
              A              
                               
-- Keep digital multimeter (Fluke 83 or equivalent) set to AC volt range-- Using connector test kit VW 1594, connect multimeter red test lead to vehicle speed signal terminal -2-, on instrument cluster-- Connect multimeter black test lead to socket 14 of VAG 1598 test box-- Rotate left front wheel
  • Voltage must vary between 1.0-4.5 V (vehicle speed signal present)
Yes No
                               
Speedometer faulty   Printed circuit board faulty
-- Replace speedometer SPEEDOMETER    -- Replace printed circuit board PRINTED CIRCUIT 
                               
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Tachometer does not work

                                           
-- Remove instrument cluster INSTRUMENT CLUSTER -- Remove red and green 26-point connectors from instrument cluster-- Check connectors for bent terminals, repair as necessary-- Connect adapter harness : VAG1598/4  to green 26-point instrument cluster connector-- Connect adapter harness to instrument cluster and VAG 1598 test box-- Connect engine tester VW 1367 for engine speed (RPM) measurement-- Connect green wire from engine tester to socket 12 of VAG 1598 test box-- Start engine
  • RPM is displayed on tester VW 1367
Yes   No
                                           
      Go to A             -- Check for open circuit in wiring to tachometer according to wiring diagram, repair as necessary  
                           
                                       
                                End        
                                           
      A                      
                               
-- Switch ignition OFF-- Remove adapter harness : VAG1598/4  from instrument cluster-- Remove cover from rear of instrument cluster COVER -- Reconnect adapter harness : VAG1598/4  to green 26-point instrument cluster connector-- Set multimeter (Fluke 83 or equivalent) to measure resistance (Ω)-- Connect multimeter between terminals -1- and -2-, then terminals -3- and -4-
  • Must be 250-350 ohms (Ω) in each case
           
Yes No, ∞ Ω (no continuity) is displayed   Tachometer faulty
      -- Replace tachometer TACHOMETER 
                     
Printed circuit board faulty            
-- Replace printed circuit board PRINTED CIRCUIT             
                               
        End               End