Workshop Manuals Factory service & repair Alfa Romeo
Alfa Romeo 156 Factory Service Manual (1997-2002)16 · Fault diagnosis
16 · Diagnostics

K03 Speedmeter not working

Make
Alfa Romeo
Model
156 Factory Service Manual
Year
1997–2002
Section
Instruments › K03 Speedmeter not working
Fault diagnosisK03 Speedmeter not working

K03 Speedmeter not working

With the ignition key ON, the speedometer does not work or works irregularly

StepTest procedureResultAction
1CHECK SPEEDOMETER ELECTRICAL CIRCUIT

Check, in order:

  • connection between speedometer and ABS control unit
  • service fuse
  • ignition-operated service fuse
  • the speedometer supply
  • speedometer earth

(Wiring diagram E4021 SPEEDOMETER ).

OK

Move onto step 2

Component defective
  • Replace the component involved (if a fuse is involved, search for the cause of the problem)

End of diagnosis

Connections broken
  • Restore the connections (

End of diagnosis

2CHECK WITH DIAGNOSTIC EQUIPMENT

Connect the diagnostic equipment (Examiner or other instruments) to the diagnostic socket

Check that there are no faults in the ABS control unit. In particular, check the speedometer signal is sent properly by the control unit. The signal is pulse-type: two pulses per wheel revolution

OK

Move onto step 3

Signal not sent
  • Check the ABS control unit and replace if necessary Op. 3340A12

End of diagnosis

3SPEEDOMETER CHECK

Check the operation of the speedometer: see DESCRIPTION AND OPERATION: 5560 Instruments (see 5560F)

OK

Move onto step 4

Instrument not working

End of diagnosis

4CHECK CORRECT OPERATION

Check that the fault is no longer present

OK

End of diagnosis

Fault persists

Incorrect selection of diagnostic procedure

Parts & tools for this job For 1997 Alfa Romeo 156

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