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Home >> Mazda >> 2023 >> MX-5 Miata Club >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> On-Board Diagnostic - Start Stop Unit >> DTC U0001-88/U0100-00/U0101-00/U0121-00/U0121-87/U0131-00/U0140-00/U0146-00/U0151-00/U0155-00: Communication Error [Start Stop Unit] >> Notes
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DTC U0001-88/U0100-00/U0101-00/U0121-00/U0121-87/U0131-00/U0140-00/U0146-00/U0151-00/U0155-00: Communication Error [Start Stop Unit]: Notes

DTC U0001:88/U0100:00/U0101:00/U0121:00/U0121:87/U0131:00/U0140:00/U0146:00/U0151:00/U0155:00 (START STOP UNIT) DETECTION CONDITION AND POSSIBLE CAUSE

Description
  • U0001:88
    • Module communication error (HS-CAN)
  • U0100:00
    • Communication error with PCM
  • U0101:00
    • Communication error with TCM
  • U0121:00
    • Communication error with DSC HU/Control Module
  • U0121:87
    • Communication error with DSC HU/Control Module
  • U0131:00
    • Communication error with electric power steering (EPS) control module
  • U0140:00
    • Communication error with BCM
  • U0146:00
    • Communication error with BCM
  • U0151:00
    • Communication error with SAS control module
  • U0155:00
    • Communication error with instrument cluster
Detection condition
  • U0001:88
    • Start stop unit detects the CAN bus communication line (HS-CAN) malfunction 10 times continuously with the ignition switched ON (engine off or on).
  • U0100:00
    • Start stop unit could not receive the CAN signal from the PCM for 1 s or more with the ignition switched ON (engine off or on).
  • U0101:00
    • Start stop unit could not receive the CAN signal from the TCM for 1 s or more with the ignition switched ON (engine off or on).
  • U0121:00
    • Start stop unit could not receive the CAN signal from the DSC HU/Control Module for 1 s or more with the ignition switched ON (engine off or on).
  • U0121:87
    • Start stop unit could not receive the CAN signal from the DSC HU/Control Module for 10 s or more with the ignition switched off.
  • U0131:00
    • Start stop unit could not receive the CAN signal from the electric power steering (EPS) control module for 1.2 s or more with the ignition switched ON (engine off or on).
  • U0140:00
    • Start stop unit could not receive the CAN signal from the BCM for 5 s or more with the ignition switched ON (engine off or on).
  • U0146:00
    • Start stop unit could not receive the CAN signal from the BCM for 5 s or more with the ignition switched ON (engine off or on).
  • U0151:00
    • Start stop unit could not receive the CAN signal from the SAS control module for 1 s or more with the ignition switched ON (engine off or on).
  • U0155:00
    • Start stop unit could not receive the CAN signal from the instrument cluster for 5 s or more with the ignition switched ON (engine off or on).
Fail-safe
  • U0001:88
    • Sets to default signal.
  • U0100:00
    • Sets to default signal.
  • U0101:00
    • Sets to default signal.
  • U0121:00
    • Sets to default signal.
  • U0121:87
    • Sets to default signal.
  • U0131:00
    • Sets to default signal.
  • U0140:00
    • Sets to default signal.
  • U0146:00
    • Sets to default signal.
  • U0151:00
    • Sets to default signal.
  • U0155:00
    • Sets to default signal.
Possible cause
  • Malfunction in CAN bus communication line
  • Malfunction in CAN line between PCM and start stop unit
  • Malfunction in CAN line between TCM and start stop unit
  • Malfunction in CAN line between DSC HU/Control Module and start stop unit
  • Malfunction in CAN line between electric power steering (EPS) control module and start stop unit
  • Malfunction in CAN line between BCM and start stop unit
  • Malfunction in CAN line between SAS control module and start stop unit
  • Malfunction in CAN line between instrument cluster and start stop unit
System wiring diagram Not applicable
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