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Home / DTC / U0123 — Lost Communication With Yaw Rate Sensor Module

U0123 — Lost Communication With Yaw Rate Sensor Module

Detailed page for trouble code U0123.

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U0123

Generic U — Network/User

Lost Communication With Yaw Rate Sensor Module

Brand: Generic
Type: U — Network/User
Views: UK: 17 EN: 27 RU: 34
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Open, short or high-resistance in CAN/communication wiring between yaw rate sensor and network
  • Yaw rate sensor module power supply (fuse, relay, wiring) or ground fault
  • Corroded, damaged, or unplugged connector at the sensor or gateway module
  • Faulty yaw rate sensor/module electronics or internal failure
  • Network termination or bus wiring fault (missing/shorted termination resistor)
  • ECU/gateway or other module on same CAN bus pulling bus off (bus-off condition)

Symptoms

  • Malfunction Indicator Lamp (MIL) or stability/ESC/ABS warning lamp illuminated
  • Loss or disablement of ESC/traction control/stability features
  • Diagnostic trouble code U0123 (may be accompanied by other U-codes)
  • Yaw rate/vehicle dynamics data unavailable in scan tool or inconsistent/erratic values
  • Possible reduced braking/stability performance messages or limp-home behavior in some vehicles

What to check

  • Use a scan tool and read all stored/pending U- and C-codes; note freeze-frame and related codes
  • Verify whether the yaw rate sensor module responds to bi-directional test/communication via OEM scanner
  • Check battery voltage and ground quality; ensure stable supply (vehicle off and accessory states as required)
  • Inspect fuses and relays related to the yaw rate sensor and vehicle network/gateway
  • Visually inspect wiring harness and connectors at the yaw rate sensor, gateway/ABS/ESC module, and junctions for damage, corrosion, moisture, chafing or broken pins
  • Check CAN bus idle voltages with a digital multimeter at the sensor connector: both lines typically ~2.5 V (recessive)

Signal parameters

  • Yaw sensor module supply voltage: nominal vehicle battery range ~9–16 V (12 V systems)
  • CAN bus idle: both CAN_H and CAN_L ≈ 2.5 V (recessive)
  • CAN bus dominant: CAN_H ≈ 3.5 V, CAN_L ≈ 1.5 V (values may vary by manufacturer)
  • Typical CAN bus termination: ≈60 Ω across CAN_H and CAN_L (two 120 Ω in parallel)
  • Common CAN speeds: 250 kbps or 500 kbps (verify vehicle-specific bus speed)
  • Module ground resistance: low (near 0 Ω to chassis ground); high resistance indicates poor ground

Diagnostic algorithm

  1. Connect an OEM-compatible scan tool; record U0123 plus any related codes and freeze-frame data.
  2. Attempt to communicate directly with the yaw rate sensor module using the tool. Note if module responds, reports data, or is absent.
  3. Check battery voltage and relevant fuses/relays for the sensor/module circuit; replace any blown fuses.
  4. Visually inspect connectors and harness from the sensor to gateway/ABS for damage, corrosion, water intrusion or disconnected plugs; repair as needed.
  5. With ignition on, measure power and ground at the sensor connector. Verify proper supply voltage and a solid ground.
  6. Measure CAN_H and CAN_L voltages at the sensor connector with a multimeter (both ≈2.5 V idle). If abnormal, inspect wiring and terminations.
  7. Use an oscilloscope or CAN bus analyzer to observe CAN frames at the sensor and at the gateway/ABS. Look for missing messages, bus errors, or bus-off events and identify which node is silent or driving errors.
  8. Check termination resistance across the CAN pair (≈60 Ω). Repair open or incorrect termination.
  9. If wiring/power/ground are good but no communication, attempt to communicate with the sensor from another node or replace/scan-flash the gateway if manufacturer procedure requires.
  10. If a suspect module is confirmed faulty after all network and wiring checks, replace the yaw rate sensor module and perform any required pairing/calibration and software updates.
  11. Clear codes and perform a road test to verify repair and that the sensor reports valid yaw-rate data and that stability/ABS systems operate normally.

Likely causes

  • CAN bus wiring fault (open/short/intermittent) between yaw rate sensor and gateway/ABS module
  • Yaw rate sensor module missing power or ground (blown fuse, damaged wiring)
  • Corroded or unseated connector at the yaw rate sensor
  • Faulty yaw rate sensor module (after verifying wiring and bus)
  • Bus termination or another node causing bus-off

Fault status

⚠️ Status
Lost Communication With Yaw Rate Sensor Module — yaw-rate data unavailable. May disable stability/ESC/traction systems until communication is restored.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.0-2.5 hours

Similar codes

U0121 U0100 U0073 U0155 U0416
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Code

U0123

HYUNDAI U — Network/User

Lost Communication With Yaw Rate Sensor Module

Brand: HYUNDAI
Type: U — Network/User
Views: UK: 8 EN: 20 RU: 17
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Open, short or high-resistance in CAN/communication wiring between yaw rate sensor and network
  • Yaw rate sensor module power supply (fuse, relay, wiring) or ground fault
  • Corroded, damaged, or unplugged connector at the sensor or gateway module
  • Faulty yaw rate sensor/module electronics or internal failure
  • Network termination or bus wiring fault (missing/shorted termination resistor)
  • ECU/gateway or other module on same CAN bus pulling bus off (bus-off condition)

Symptoms

  • Malfunction Indicator Lamp (MIL) or stability/ESC/ABS warning lamp illuminated
  • Loss or disablement of ESC/traction control/stability features
  • Diagnostic trouble code U0123 (may be accompanied by other U-codes)
  • Yaw rate/vehicle dynamics data unavailable in scan tool or inconsistent/erratic values
  • Possible reduced braking/stability performance messages or limp-home behavior in some vehicles

What to check

  • Use a scan tool and read all stored/pending U- and C-codes; note freeze-frame and related codes
  • Verify whether the yaw rate sensor module responds to bi-directional test/communication via OEM scanner
  • Check battery voltage and ground quality; ensure stable supply (vehicle off and accessory states as required)
  • Inspect fuses and relays related to the yaw rate sensor and vehicle network/gateway
  • Visually inspect wiring harness and connectors at the yaw rate sensor, gateway/ABS/ESC module, and junctions for damage, corrosion, moisture, chafing or broken pins
  • Check CAN bus idle voltages with a digital multimeter at the sensor connector: both lines typically ~2.5 V (recessive)

Signal parameters

  • Yaw sensor module supply voltage: nominal vehicle battery range ~9–16 V (12 V systems)
  • CAN bus idle: both CAN_H and CAN_L ≈ 2.5 V (recessive)
  • CAN bus dominant: CAN_H ≈ 3.5 V, CAN_L ≈ 1.5 V (values may vary by manufacturer)
  • Typical CAN bus termination: ≈60 Ω across CAN_H and CAN_L (two 120 Ω in parallel)
  • Common CAN speeds: 250 kbps or 500 kbps (verify vehicle-specific bus speed)
  • Module ground resistance: low (near 0 Ω to chassis ground); high resistance indicates poor ground

Diagnostic algorithm

  1. Connect an OEM-compatible scan tool; record U0123 plus any related codes and freeze-frame data.
  2. Attempt to communicate directly with the yaw rate sensor module using the tool. Note if module responds, reports data, or is absent.
  3. Check battery voltage and relevant fuses/relays for the sensor/module circuit; replace any blown fuses.
  4. Visually inspect connectors and harness from the sensor to gateway/ABS for damage, corrosion, water intrusion or disconnected plugs; repair as needed.
  5. With ignition on, measure power and ground at the sensor connector. Verify proper supply voltage and a solid ground.
  6. Measure CAN_H and CAN_L voltages at the sensor connector with a multimeter (both ≈2.5 V idle). If abnormal, inspect wiring and terminations.
  7. Use an oscilloscope or CAN bus analyzer to observe CAN frames at the sensor and at the gateway/ABS. Look for missing messages, bus errors, or bus-off events and identify which node is silent or driving errors.
  8. Check termination resistance across the CAN pair (≈60 Ω). Repair open or incorrect termination.
  9. If wiring/power/ground are good but no communication, attempt to communicate with the sensor from another node or replace/scan-flash the gateway if manufacturer procedure requires.
  10. If a suspect module is confirmed faulty after all network and wiring checks, replace the yaw rate sensor module and perform any required pairing/calibration and software updates.
  11. Clear codes and perform a road test to verify repair and that the sensor reports valid yaw-rate data and that stability/ABS systems operate normally.

Likely causes

  • CAN bus wiring fault (open/short/intermittent) between yaw rate sensor and gateway/ABS module
  • Yaw rate sensor module missing power or ground (blown fuse, damaged wiring)
  • Corroded or unseated connector at the yaw rate sensor
  • Faulty yaw rate sensor module (after verifying wiring and bus)
  • Bus termination or another node causing bus-off

Fault status

⚠️ Status
Lost Communication With Yaw Rate Sensor Module — yaw-rate data unavailable. May disable stability/ESC/traction systems until communication is restored.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.0-2.5 hours

Similar codes

U0121 U0100 U0073 U0155 U0416
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email
Code

U0123

LAND ROVER U — Network/User

Lost communication with the yaw rate sensor module

Brand: LAND ROVER
Type: U — Network/User
Views: UK: 5 EN: 14 RU: 13
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Open, short or high-resistance in CAN/communication wiring between yaw rate sensor and network
  • Yaw rate sensor module power supply (fuse, relay, wiring) or ground fault
  • Corroded, damaged, or unplugged connector at the sensor or gateway module
  • Faulty yaw rate sensor/module electronics or internal failure
  • Network termination or bus wiring fault (missing/shorted termination resistor)
  • ECU/gateway or other module on same CAN bus pulling bus off (bus-off condition)

Symptoms

  • Malfunction Indicator Lamp (MIL) or stability/ESC/ABS warning lamp illuminated
  • Loss or disablement of ESC/traction control/stability features
  • Diagnostic trouble code U0123 (may be accompanied by other U-codes)
  • Yaw rate/vehicle dynamics data unavailable in scan tool or inconsistent/erratic values
  • Possible reduced braking/stability performance messages or limp-home behavior in some vehicles

What to check

  • Use a scan tool and read all stored/pending U- and C-codes; note freeze-frame and related codes
  • Verify whether the yaw rate sensor module responds to bi-directional test/communication via OEM scanner
  • Check battery voltage and ground quality; ensure stable supply (vehicle off and accessory states as required)
  • Inspect fuses and relays related to the yaw rate sensor and vehicle network/gateway
  • Visually inspect wiring harness and connectors at the yaw rate sensor, gateway/ABS/ESC module, and junctions for damage, corrosion, moisture, chafing or broken pins
  • Check CAN bus idle voltages with a digital multimeter at the sensor connector: both lines typically ~2.5 V (recessive)

Signal parameters

  • Yaw sensor module supply voltage: nominal vehicle battery range ~9–16 V (12 V systems)
  • CAN bus idle: both CAN_H and CAN_L ≈ 2.5 V (recessive)
  • CAN bus dominant: CAN_H ≈ 3.5 V, CAN_L ≈ 1.5 V (values may vary by manufacturer)
  • Typical CAN bus termination: ≈60 Ω across CAN_H and CAN_L (two 120 Ω in parallel)
  • Common CAN speeds: 250 kbps or 500 kbps (verify vehicle-specific bus speed)
  • Module ground resistance: low (near 0 Ω to chassis ground); high resistance indicates poor ground

Diagnostic algorithm

  1. Connect an OEM-compatible scan tool; record U0123 plus any related codes and freeze-frame data.
  2. Attempt to communicate directly with the yaw rate sensor module using the tool. Note if module responds, reports data, or is absent.
  3. Check battery voltage and relevant fuses/relays for the sensor/module circuit; replace any blown fuses.
  4. Visually inspect connectors and harness from the sensor to gateway/ABS for damage, corrosion, water intrusion or disconnected plugs; repair as needed.
  5. With ignition on, measure power and ground at the sensor connector. Verify proper supply voltage and a solid ground.
  6. Measure CAN_H and CAN_L voltages at the sensor connector with a multimeter (both ≈2.5 V idle). If abnormal, inspect wiring and terminations.
  7. Use an oscilloscope or CAN bus analyzer to observe CAN frames at the sensor and at the gateway/ABS. Look for missing messages, bus errors, or bus-off events and identify which node is silent or driving errors.
  8. Check termination resistance across the CAN pair (≈60 Ω). Repair open or incorrect termination.
  9. If wiring/power/ground are good but no communication, attempt to communicate with the sensor from another node or replace/scan-flash the gateway if manufacturer procedure requires.
  10. If a suspect module is confirmed faulty after all network and wiring checks, replace the yaw rate sensor module and perform any required pairing/calibration and software updates.
  11. Clear codes and perform a road test to verify repair and that the sensor reports valid yaw-rate data and that stability/ABS systems operate normally.

Likely causes

  • CAN bus wiring fault (open/short/intermittent) between yaw rate sensor and gateway/ABS module
  • Yaw rate sensor module missing power or ground (blown fuse, damaged wiring)
  • Corroded or unseated connector at the yaw rate sensor
  • Faulty yaw rate sensor module (after verifying wiring and bus)
  • Bus termination or another node causing bus-off

Fault status

⚠️ Status
Lost Communication With Yaw Rate Sensor Module — yaw-rate data unavailable. May disable stability/ESC/traction systems until communication is restored.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.0-2.5 hours

Similar codes

U0121 U0100 U0073 U0155 U0416
Workshop Manuals

Repair manuals for LAND ROVER

3

Land Rover Defender 300Tdi — Workshop Manual (1996 model year)

Workshop Manual
Defender 300Tdi Years: 1996 Manual in English 7.5 MB
Short description

Official workshop manual for the Land Rover Defender 300Tdi (from 1996 model year). Contains specifications, adjustment, fault diagnosis and step-by-step repair and overhaul procedures for engine, transmission, axles, suspension, brakes, electrical and body. Intended for dealer workshops and trained technicians.

Contents
Key sections:
  • 01 INTRODUCTION
  • 04 GENERAL SPECIFICATION DATA
  • 05 ENGINE TUNING DATA
  • 07 GENERAL FITTING REMINDERS
  • 09 LUBRICANTS, FLUIDS AND CAPACITIES
  • 10 MAINTENANCE
  • 12 ENGINE Tdi
  • - Description and operation
  • - Fault diagnosis
  • - Adjustment
  • - Repair and overhaul procedures
  • 19 FUEL SYSTEM Tdi
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Land Rover Defender Workshop Manual Supplement & Body Repair Manual (1999 & 2002 MY)

Workshop Manual
Defender Years: 1999–2002 Manual in English 7.6 MB
Short description

Workshop Manual Supplement and Body Repair Manual for the Land Rover Defender. Includes general specifications, maintenance schedules, tuning data and step‑by‑step repair procedures for engine, transmission, suspension, brakes, electrical and body repairs. Covers Defender models from 1999 and 2002 model years.

Contents
Key sections:
  • 01 - INTRODUCTION
  • - Introduction
  • - Dimensions
  • - References
  • - Repairs and replacements
  • - Poisonous substances
  • - Fuel handling precautions
  • - Synthetic rubber
  • - Recommended sealants
  • - Used engine oil precautions
  • - Accessories and conversions
  • - Wheels and tyres
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Land Rover Range Rover — Electrical Library (LRL 0453ENG, 2002)

Workshop Manual
Manual in English Pages: 494 7.1 MB
Short description

Land Rover Range Rover Electrical Library (LRL 0453ENG). Comprehensive manual covering fuse details, earth points, system descriptions, diagnostics and connector pin-outs for electrical troubleshooting and repair. Intended for technicians and service workshops.

Contents
Key sections:
  • 1 INTRODUCTION
  • 1.1 About this document
  • 1.2 Battery voltage
  • 1.3 Electrical precautions
  • 1.4 Battery disconnecting / charging
  • 1.5 Disciplines / greases
  • 1.6 Abbreviations
  • 1.7 HeVAC, sensors abbreviations
  • 1.8 How to use this document
  • 1.9 Connector detail format
  • 1.10 Fault diagnosis
  • 1.11 Wire colour codes
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