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C0045 — Left rear wheel speed sensor circuit malfunction

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Code

C0045

DAEWOO C — Chassis

Left rear wheel speed sensor circuit malfunction

Brand: DAEWOO
Views: UK: 2 EN: 15 RU: 12
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Damaged or contaminated wheel speed sensor
  • Broken, chafed or corroded wiring or connector to the sensor
  • Loose or corroded connector pins
  • Damaged or missing tone ring (reluctor) or foreign material between sensor and ring
  • Faulty ABS/traction control module or poor ground
  • Short to voltage or ground in the sensor circuit

Symptoms

  • ABS warning lamp illuminated
  • Traction control/ESC warning or reduced functionality
  • Left rear wheel speed reading erratic or zero in live data
  • Unwanted ABS activation or loss of anti-lock braking function under braking
  • Possible speedometer/vehicle speed inconsistencies on some models

What to check

  • Use a scan tool to read ABS/traction control live data and confirm left rear wheel speed reading vs other wheels.
  • Visually inspect sensor, wiring harness and connector for damage, corrosion or contamination.
  • Check connector for proper seating and bent or pushed-back pins.
  • Spin the wheel by hand (vehicle safely supported) and observe live wheel speed value or measure sensor signal.
  • Measure sensor resistance and compare to specification.
  • Backprobe connector and check for reference voltage (if active sensor) or AC output (if passive) while spinning wheel.

Signal parameters

  • Passive (variable-reluctance) sensors: DC resistance typically ~500–1500 Ω (model dependent); AC voltage rises with speed (tens to hundreds of millivolts at low speed up to volts at higher speed).
  • Active (Hall) sensors: provide a digital/pulse signal, often 0–5 V or 0–12 V square wave; reference/ground supply typically 5–12 V from ABS module.
  • Pulse frequency proportional to wheel speed; expect smooth, regular waveform without dropouts when wheel is rotated.
  • Expected waveform at connector: clean sinusoidal/AC for passive sensors or square/pulse for active sensors; intermittent, clipped or absent waveform indicates fault.

Diagnostic algorithm

  1. Confirm fault with a scan tool and record freeze frame/live data for left rear wheel speed.
  2. Visually inspect left rear sensor, housing, tone ring and wiring for damage, dirt or metal shavings; clean sensor and tone ring if contaminated.
  3. With vehicle safely supported, spin the left rear wheel and observe wheel speed value in the scan tool to confirm missing/erratic signal.
  4. Disconnect sensor connector and inspect pins for corrosion, bent pins or water ingress.
  5. Measure sensor resistance with an ohmmeter (compare to factory spec). An open or short indicates sensor replacement.
  6. For passive sensor: backprobe sensor connector and spin wheel; measure AC voltage with a multimeter or oscilloscope. For active sensor: check reference voltage at connector (typically 5–12 V) and measure output waveform while spinning.
  7. Wiggle wiring and connectors while monitoring signal to find intermittent faults; check continuity from sensor connector to ABS module pins to rule out open circuits.
  8. Inspect tone ring for cracks, missing teeth, heavy corrosion or foreign material; repair or replace if damaged.
  9. Repair or replace damaged wiring, connector or sensor as required. After repairs clear codes, perform a test drive and re-scan to confirm the fault does not return.
  10. If wiring and sensor are good but no signal at the ABS module, test module inputs and grounds; consider module repair/replacement only after wiring and sensor verified good.

Likely causes

  • Dirty or damaged sensor air gap/tone ring interference
  • Open or short in the sensor wiring or poor connector contact
  • Failed wheel speed sensor element (magnetic or Hall)
  • Corroded connector or grounding problem

Fault status

⚠️ Status
ABS/traction control module detected a malfunction in the left rear wheel speed sensor circuit; ABS warning lamp stored and vehicle stability systems may be limited.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

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Code

C0045

Generic C — Chassis

Brake Pressure Sensor B

Brand: Generic
Views: UK: 24 EN: 45 RU: 48
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Damaged or contaminated wheel speed sensor
  • Broken, chafed or corroded wiring or connector to the sensor
  • Loose or corroded connector pins
  • Damaged or missing tone ring (reluctor) or foreign material between sensor and ring
  • Faulty ABS/traction control module or poor ground
  • Short to voltage or ground in the sensor circuit

Symptoms

  • ABS warning lamp illuminated
  • Traction control/ESC warning or reduced functionality
  • Left rear wheel speed reading erratic or zero in live data
  • Unwanted ABS activation or loss of anti-lock braking function under braking
  • Possible speedometer/vehicle speed inconsistencies on some models

What to check

  • Use a scan tool to read ABS/traction control live data and confirm left rear wheel speed reading vs other wheels.
  • Visually inspect sensor, wiring harness and connector for damage, corrosion or contamination.
  • Check connector for proper seating and bent or pushed-back pins.
  • Spin the wheel by hand (vehicle safely supported) and observe live wheel speed value or measure sensor signal.
  • Measure sensor resistance and compare to specification.
  • Backprobe connector and check for reference voltage (if active sensor) or AC output (if passive) while spinning wheel.

Signal parameters

  • Passive (variable-reluctance) sensors: DC resistance typically ~500–1500 Ω (model dependent); AC voltage rises with speed (tens to hundreds of millivolts at low speed up to volts at higher speed).
  • Active (Hall) sensors: provide a digital/pulse signal, often 0–5 V or 0–12 V square wave; reference/ground supply typically 5–12 V from ABS module.
  • Pulse frequency proportional to wheel speed; expect smooth, regular waveform without dropouts when wheel is rotated.
  • Expected waveform at connector: clean sinusoidal/AC for passive sensors or square/pulse for active sensors; intermittent, clipped or absent waveform indicates fault.

Diagnostic algorithm

  1. Confirm fault with a scan tool and record freeze frame/live data for left rear wheel speed.
  2. Visually inspect left rear sensor, housing, tone ring and wiring for damage, dirt or metal shavings; clean sensor and tone ring if contaminated.
  3. With vehicle safely supported, spin the left rear wheel and observe wheel speed value in the scan tool to confirm missing/erratic signal.
  4. Disconnect sensor connector and inspect pins for corrosion, bent pins or water ingress.
  5. Measure sensor resistance with an ohmmeter (compare to factory spec). An open or short indicates sensor replacement.
  6. For passive sensor: backprobe sensor connector and spin wheel; measure AC voltage with a multimeter or oscilloscope. For active sensor: check reference voltage at connector (typically 5–12 V) and measure output waveform while spinning.
  7. Wiggle wiring and connectors while monitoring signal to find intermittent faults; check continuity from sensor connector to ABS module pins to rule out open circuits.
  8. Inspect tone ring for cracks, missing teeth, heavy corrosion or foreign material; repair or replace if damaged.
  9. Repair or replace damaged wiring, connector or sensor as required. After repairs clear codes, perform a test drive and re-scan to confirm the fault does not return.
  10. If wiring and sensor are good but no signal at the ABS module, test module inputs and grounds; consider module repair/replacement only after wiring and sensor verified good.

Likely causes

  • Dirty or damaged sensor air gap/tone ring interference
  • Open or short in the sensor wiring or poor connector contact
  • Failed wheel speed sensor element (magnetic or Hall)
  • Corroded connector or grounding problem

Fault status

⚠️ Status
ABS/traction control module detected a malfunction in the left rear wheel speed sensor circuit; ABS warning lamp stored and vehicle stability systems may be limited.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

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Code

C0045

HUMMER C — Chassis

Left Rear Wheel Speed Circuit Malfunction

Brand: HUMMER
Views: UK: 8 EN: 16 RU: 27
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Damaged or contaminated wheel speed sensor
  • Broken, chafed or corroded wiring or connector to the sensor
  • Loose or corroded connector pins
  • Damaged or missing tone ring (reluctor) or foreign material between sensor and ring
  • Faulty ABS/traction control module or poor ground
  • Short to voltage or ground in the sensor circuit

Symptoms

  • ABS warning lamp illuminated
  • Traction control/ESC warning or reduced functionality
  • Left rear wheel speed reading erratic or zero in live data
  • Unwanted ABS activation or loss of anti-lock braking function under braking
  • Possible speedometer/vehicle speed inconsistencies on some models

What to check

  • Use a scan tool to read ABS/traction control live data and confirm left rear wheel speed reading vs other wheels.
  • Visually inspect sensor, wiring harness and connector for damage, corrosion or contamination.
  • Check connector for proper seating and bent or pushed-back pins.
  • Spin the wheel by hand (vehicle safely supported) and observe live wheel speed value or measure sensor signal.
  • Measure sensor resistance and compare to specification.
  • Backprobe connector and check for reference voltage (if active sensor) or AC output (if passive) while spinning wheel.

Signal parameters

  • Passive (variable-reluctance) sensors: DC resistance typically ~500–1500 Ω (model dependent); AC voltage rises with speed (tens to hundreds of millivolts at low speed up to volts at higher speed).
  • Active (Hall) sensors: provide a digital/pulse signal, often 0–5 V or 0–12 V square wave; reference/ground supply typically 5–12 V from ABS module.
  • Pulse frequency proportional to wheel speed; expect smooth, regular waveform without dropouts when wheel is rotated.
  • Expected waveform at connector: clean sinusoidal/AC for passive sensors or square/pulse for active sensors; intermittent, clipped or absent waveform indicates fault.

Diagnostic algorithm

  1. Confirm fault with a scan tool and record freeze frame/live data for left rear wheel speed.
  2. Visually inspect left rear sensor, housing, tone ring and wiring for damage, dirt or metal shavings; clean sensor and tone ring if contaminated.
  3. With vehicle safely supported, spin the left rear wheel and observe wheel speed value in the scan tool to confirm missing/erratic signal.
  4. Disconnect sensor connector and inspect pins for corrosion, bent pins or water ingress.
  5. Measure sensor resistance with an ohmmeter (compare to factory spec). An open or short indicates sensor replacement.
  6. For passive sensor: backprobe sensor connector and spin wheel; measure AC voltage with a multimeter or oscilloscope. For active sensor: check reference voltage at connector (typically 5–12 V) and measure output waveform while spinning.
  7. Wiggle wiring and connectors while monitoring signal to find intermittent faults; check continuity from sensor connector to ABS module pins to rule out open circuits.
  8. Inspect tone ring for cracks, missing teeth, heavy corrosion or foreign material; repair or replace if damaged.
  9. Repair or replace damaged wiring, connector or sensor as required. After repairs clear codes, perform a test drive and re-scan to confirm the fault does not return.
  10. If wiring and sensor are good but no signal at the ABS module, test module inputs and grounds; consider module repair/replacement only after wiring and sensor verified good.

Likely causes

  • Dirty or damaged sensor air gap/tone ring interference
  • Open or short in the sensor wiring or poor connector contact
  • Failed wheel speed sensor element (magnetic or Hall)
  • Corroded connector or grounding problem

Fault status

⚠️ Status
ABS/traction control module detected a malfunction in the left rear wheel speed sensor circuit; ABS warning lamp stored and vehicle stability systems may be limited.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

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Code

C0045

HYUNDAI C — Chassis

Wheel Speed Sensor Rear-LH Circuit Malfunction

Brand: HYUNDAI
Views: UK: 14 EN: 23 RU: 34
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Damaged or contaminated wheel speed sensor
  • Broken, chafed or corroded wiring or connector to the sensor
  • Loose or corroded connector pins
  • Damaged or missing tone ring (reluctor) or foreign material between sensor and ring
  • Faulty ABS/traction control module or poor ground
  • Short to voltage or ground in the sensor circuit

Symptoms

  • ABS warning lamp illuminated
  • Traction control/ESC warning or reduced functionality
  • Left rear wheel speed reading erratic or zero in live data
  • Unwanted ABS activation or loss of anti-lock braking function under braking
  • Possible speedometer/vehicle speed inconsistencies on some models

What to check

  • Use a scan tool to read ABS/traction control live data and confirm left rear wheel speed reading vs other wheels.
  • Visually inspect sensor, wiring harness and connector for damage, corrosion or contamination.
  • Check connector for proper seating and bent or pushed-back pins.
  • Spin the wheel by hand (vehicle safely supported) and observe live wheel speed value or measure sensor signal.
  • Measure sensor resistance and compare to specification.
  • Backprobe connector and check for reference voltage (if active sensor) or AC output (if passive) while spinning wheel.

Signal parameters

  • Passive (variable-reluctance) sensors: DC resistance typically ~500–1500 Ω (model dependent); AC voltage rises with speed (tens to hundreds of millivolts at low speed up to volts at higher speed).
  • Active (Hall) sensors: provide a digital/pulse signal, often 0–5 V or 0–12 V square wave; reference/ground supply typically 5–12 V from ABS module.
  • Pulse frequency proportional to wheel speed; expect smooth, regular waveform without dropouts when wheel is rotated.
  • Expected waveform at connector: clean sinusoidal/AC for passive sensors or square/pulse for active sensors; intermittent, clipped or absent waveform indicates fault.

Diagnostic algorithm

  1. Confirm fault with a scan tool and record freeze frame/live data for left rear wheel speed.
  2. Visually inspect left rear sensor, housing, tone ring and wiring for damage, dirt or metal shavings; clean sensor and tone ring if contaminated.
  3. With vehicle safely supported, spin the left rear wheel and observe wheel speed value in the scan tool to confirm missing/erratic signal.
  4. Disconnect sensor connector and inspect pins for corrosion, bent pins or water ingress.
  5. Measure sensor resistance with an ohmmeter (compare to factory spec). An open or short indicates sensor replacement.
  6. For passive sensor: backprobe sensor connector and spin wheel; measure AC voltage with a multimeter or oscilloscope. For active sensor: check reference voltage at connector (typically 5–12 V) and measure output waveform while spinning.
  7. Wiggle wiring and connectors while monitoring signal to find intermittent faults; check continuity from sensor connector to ABS module pins to rule out open circuits.
  8. Inspect tone ring for cracks, missing teeth, heavy corrosion or foreign material; repair or replace if damaged.
  9. Repair or replace damaged wiring, connector or sensor as required. After repairs clear codes, perform a test drive and re-scan to confirm the fault does not return.
  10. If wiring and sensor are good but no signal at the ABS module, test module inputs and grounds; consider module repair/replacement only after wiring and sensor verified good.

Likely causes

  • Dirty or damaged sensor air gap/tone ring interference
  • Open or short in the sensor wiring or poor connector contact
  • Failed wheel speed sensor element (magnetic or Hall)
  • Corroded connector or grounding problem

Fault status

⚠️ Status
ABS/traction control module detected a malfunction in the left rear wheel speed sensor circuit; ABS warning lamp stored and vehicle stability systems may be limited.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

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