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OBD II Fault Code P1656 :

Description of Fault code P1656

OTHER UNIT SIGNAL FAILURE

Possible failuer P1656

  • Signal line open
  • Signal line short
  • VSA control unit failure

Diagnostic Procedure using AutoHex II Scan Tool

  • The PCM/ TCM monitors the actual mainshaft speed (rpm) and countershaft speed (rpm) ratios and the commanded ratio. The PCM/TCM computes these ratio continuously.
  • A malfunction is detected when a difference between the actual ratio and the commanded ratio occurs, and it is over the specific ratio.
  • When the 3rd -> 4th upshift has been made then the PCM/TCM detects neutral position while driving in 5th gear a malfunction is detected.

Test Conditions using AutoHex tester

  • D or D3 shift position
  • Battery Voltage > 11V
  • Upshifting 1st through 5th

Clear Fault codes Conditions

  • The PCM/ TCM monitors the actual mainshaft speed (rpm) and countershaft speed (rpm) ratios and the commanded ratio. The PCM/TCM computes these ratio continuously.
  • A malfunction is detected when a difference between the actual ratio and the commanded ratio occurs, and it is over the specific ratio.
  • When the 3rd -> 4th upshift has been made then the PCM/TCM detects neutral position while driving in 5th gear a malfunction is detected.

MIL Status

  • OFF

BMW Key Programming


Note:

  • AutoHex II is a professional Auto diagnostic.
  • This fault code is a GERENRIC fault code, some cars may change the meaning of this fault code.
    To get the accurate fault code description you may use AutoHex II

More Fault codes:

OBD II Fault Code P1657
OBD II Fault Code P1658
OBD II Fault Code P1659
OBD II Fault Code P165A
OBD II Fault Code P165B
OBD II Fault Code P165C
OBD II Fault Code P165D
OBD II Fault Code P165E
OBD II Fault Code P165F
OBD II Fault Code P1660
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