Toggle Side Panel

Shopping Cart

No products in the basket.

Shopping Cart

No products in the basket.

Close search
Home / DTC / C0038 — Left Rear Wheel Speed Sensor Supply

C0038 — Left Rear Wheel Speed Sensor Supply

Detailed page for trouble code C0038.

33,006codes
59brands
10,545generic
22,461specific
All codes P-codes (Powertrain) B-codes (Body) C-codes (Chassis) U-codes (Network/User) Tesla Alerts
Reset
Code

C0038

Generic C — Chassis

Left Rear Wheel Speed Sensor Supply

Brand: Generic
Type: C — Chassis
Views: UK: 21 EN: 40 RU: 27
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Damaged or corroded connector at left rear wheel speed sensor
  • Broken, pinched, chafed, or shorted wiring between sensor and ABS/BCM
  • Faulty left rear wheel speed sensor (open/shorted or failed electronics)
  • Loss of reference supply or ground from ABS control module (blown fuse, bad ground)
  • Faulty ABS/traction control module or internal driver circuit
  • Intermittent connection due to water intrusion, bent terminal, or poor crimp

Symptoms

  • ABS warning lamp and/or traction control/ESP light illuminated
  • ABS or traction control may be disabled or operate in degraded mode
  • Possible braking pulsation or reduced ABS function during stops
  • Inconsistent or zero wheel speed reading for left rear on scan tool
  • Cruise control or stability control may be disabled
  • Intermittent faults that can come and go with wheel movement

What to check

  • Read freeze frame and live data with a scan tool — note left rear wheel speed value vs other wheels
  • Visual inspection of left rear sensor, harness, and connector for damage, corrosion, or water
  • Wiggle test harness and connector while monitoring live data for intermittent changes
  • Check ABS/BCM fuses and module grounds related to sensor supply
  • Back-probe the sensor connector to check reference supply voltage and ground at rest and while rotating wheel
  • Measure sensor resistance (for passive sensors) or output signal with wheel rotation

Signal parameters

  • Active (Hall/3-wire) sensors: reference supply typically ~5 V (±0.5 V). Signal toggles between ~0.5–4.5 V with wheel rotation.
  • Passive (2-wire) sensors: coil resistance commonly ~500–2,000 ohms (varies by make). Open circuit: >>10 kΩ.
  • Passive sensor AC output: small mV–V AC that increases with wheel speed (e.g., 0.2–1.5 VRMS at low speeds; higher at speed).
  • Expected signal frequency proportional to wheel speed: ~tens to hundreds of Hz depending on vehicle and speed.
  • Short to battery: near battery voltage at sensor signal pin; short to ground: ~0 V at signal/reference pin.

Diagnostic algorithm

  1. Safety: Park on level ground, chock wheels, set parking brake. Use jack stands if wheel removal is required.
  2. Scan tool: Read and record codes and live wheel speed readings. Confirm C0038 present and look for related ABS/traction codes.
  3. Visual: Inspect left rear sensor, tone ring, harness, and connector for physical damage, contamination, or missing teeth on tone ring.
  4. Wiggle Test: With ignition on (engine off) or as directed by scan tool, wiggle harness and connector while monitoring left rear wheel speed value for intermittent changes.
  5. Power & Ground: Back-probe sensor connector. With ignition on, verify reference supply voltage (typically ~5 V) and a good ground. If no supply, inspect fuses and module power/ground.
  6. Resistance/Continuity: With connector disconnected, measure sensor resistance (passive) and compare to spec. Check continuity from sensor pins to ABS module pins, and check for short to ground or battery.
  7. Dynamic Output: Spin the wheel (lift vehicle safely) and observe sensor output on oscilloscope or scan tool. For active sensor expect square/pulse; for passive expect AC waveform whose amplitude increases with speed.
  8. Isolate: If wiring and supply are good but no proper signal, replace the left rear sensor. If a known-good sensor still fails, suspect wiring harness or ABS module driver.
  9. Repair: Repair or replace damaged wiring, connector, sensor, or blown fuse. If ABS module is suspected after wiring and sensor checks, consult manufacturer procedures for module testing/replacement.
  10. Verify: Clear codes, perform a test drive and re-scan to ensure code does not return and the left rear wheel speed reads consistently with other wheels.

Likely causes

  • Corroded connector or water intrusion at the sensor harness
  • Open or short in the sensor supply wire caused by suspension movement
  • Failed wheel speed sensor (common on high-mileage vehicles)
  • Blown ABS power fuse or bad module ground
  • Internal ABS module supply/driver fault (less common)

Fault status

⚠️ Status
Left Rear Wheel Speed Sensor Supply: circuit fault detected (open/short/intermittent or supply/ground failure) causing invalid or missing left rear wheel speed input to ABS/traction control module.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

C0035 C0036 C0037 C0040 C0041
Workshop Manuals

Available brands with manuals

2
AUDI 11

6-speed manual gearbox 0B1, front-wheel drive — Workshop Manual (Edition 05.2014)

Workshop Manual
Years: 2008 Manual in English Pages: 187 4.9 MB
Short description

Workshop manual for the 6‑speed manual gearbox 0B1 (front‑wheel drive). Includes identification, technical data, gearbox/selector removal & installation procedures, clutch hydraulics, adjustment instructions and front differential service. Applicable to Audi A4, Audi A5 (Coupé, Cabriolet, Sportback) and Audi Q5 as referenced in the manual. Edition: 05.2014.

199,00 UAH
Contents
Key sections:
  • 00 - Technical data
  • 1 Identification
  • 1.1 Gearbox identification
  • 2 Technical data
  • 2.1 Allocation of gearbox to engine
  • 2.1.1 Allocation - Audi A4 2008 ►
  • 2.1.2 Allocation - Audi A5 Coupé 2008 ►, Audi A5 Sportback 2010 ►
  • 2.1.3 Allocation - Audi A5 Cabriolet 2009 ►
  • 2.1.4 Allocation - Audi Q5 2008 ►
  • 2.2 Capacities
  • 3 Transmission layout
  • 3.1 Transmission layout - front‑wheel drive
Buy

Audi A3 (1997) – 1.6L 4-cylinder (2‑valve) Engine Mechanical Components Service Manual (AEH, AKL, APF) – Edition 07.2002

Workshop Manual
Years: 1997 Manual in English Pages: 283 4.3 MB
Short description

Service manual for Audi A3 (1997) 1.6L 4‑cylinder (2‑valve) engines (codes AEH, AKL, APF). Includes technical data, engine removal/installation, crankshaft group, cylinder head and valve gear, lubrication, cooling and exhaust system procedures. Edition 07.2002.

199,00 UAH
Contents
Key sections:
  • 00 - Technical data ............................................................1
  • 1 Technical data ............................................................1
  • 1.1 Technical data .......................................................1
  • 1.2 Engine number .......................................................1
  • 1.3 Engine data ........................................................1
  • 10 - Removing and installing engine ..........................................3
  • 1 Removing and installing engine .........................................3
  • 1.1 Removing and installing engine ....................................3
  • 1.2 Removing - vehicles with engine codes AEH, AKL .....................4
  • 1.3 Removing - vehicles with engine code APF ..........................18
  • 1.4 Detaching engine from gearbox ...................................35
  • 1.5 Attaching engine to repair stand ................................38
Buy

AUDI A3 (2004) Workshop Manual — 2.0L FSI Turbo (4‑cyl, 4‑valve) Engine, Mechanics — Edition 03.2017

Workshop Manual
Years: 2004 Manual in English Pages: 235 3.8 MB
Short description

Official workshop manual for the Audi A3 2.0L FSI turbo engine (mechanics). Includes step‑by‑step removal/install procedures, technical data, tightening torques and diagnostic/repair instructions. Intended for professional garages and experienced technicians.

199,00 UAH
Contents
Key sections:
  • 00 - Technical data
  • 1 Engine number
  • 2 Engine data (code letters AXX, BPY, BWA, BHZ, BZC, CDL — capacity, power, torque, bore/stroke, compression, ignition)
  • 3 Safety precautions
  • 3.1 Working on the fuel system
  • 3.2 Procedure before opening high-pressure section
  • 3.3 Working on the cooling system
  • 3.4 Using testers during road test
  • 3.5 Working on the exhaust system
  • 4 General repair instructions
  • 4.1 Cleanliness rules for fuel/injection/turbo
  • 4.2 Checking fuel system for leaks
Buy

Audi A3 2004 — Electrical System (Workshop Manual, Edition 02.2018)

Workshop Manual
Years: 2004 Manual in English Pages: 150 68.2 MB
Short description

Workshop manual for the Audi A3 (2004) — Electrical system. Includes procedures for battery, starter, alternator, gauges, wipers, exterior/interior lighting and wiring. Edition 02.2018.

199,00 UAH
Contents
Key sections:
  • List of Workshop Manual Repair Groups
  • - 27 Starter, current supply, CCS
  • - 90 Gauges, instruments
  • - 92 Windscreen wash/wipe system
  • - 94 Lights, bulbs, switches - exterior
  • - 96 Lights, bulbs, switches - interior
  • - 97 Wiring
  • 27 - Starter, current supply, CCS
  • 1 Contact corrosion
  • 2 Battery
  • 2.1 Battery - general notes
  • 2.2 Maintenance-free batteries
Buy

Audi A4 / A4 Cabriolet – 4.2 l V8 (5‑valve, timing chains) – Workshop Manual (Mechanics) – Edition 04.2007

Workshop Manual
Years: 2001–2003 Manual in English Pages: 307 7.3 MB
Short description

Comprehensive workshop manual for Audi A4 (2001) and A4 Cabriolet (2003) with the 4.2 L V8, 5‑valve engine with timing chains (Engine IDs BBK/BHF). Includes step‑by‑step procedures for engine removal/installation, crankshaft and timing chain service, cylinder head/valve gear, lubrication, cooling and exhaust system repairs. Intended for professional technicians and service workshops.

199,00 UAH
Contents
Key sections:
  • 00 - Technical data
  • 1 Engine number
  • 2 Engine data (Codes: BBK / BHF; 4.163 l; 253 kW @7000 rpm; torque 410–420 Nm; bore 84.5 mm; stroke 92.8 mm; compression ratio 11.5; RON 98)
  • 3 Safety precautions
  • 4 General repair instructions (cleanliness, fuel system, contact corrosion)
  • 10 - Removing and installing engine
  • 1 Removing engine - vehicles with manual gearbox
  • 1.1 Removing engine (tools, drain fluids, remove bumper, lock carrier, disconnect wiring, fuel, coolant, A/C lines, suspension components, propshaft, exhaust, support engine on platform, lower assembly)
  • 1.2 Separating engine and gearbox (subframe removal, support sets, remove front exhaust pipes, bolt sequence)
  • 1.3 Securing engine to engine and gearbox stand (lifting tackle, VAS 6095 support)
  • 1.4 Installing engine (clutch remarks, alignment, torque values)
  • 2 Removing and installing engine - vehicles with automatic gearbox (procedure parallels manual gearbox with ATF/torque converter notes)
Buy

Audi A4 / A4 Cabriolet — Auxiliary Heater Workshop Manual (Edition 08.2004)

Workshop Manual
Years: 2001 Manual in English Pages: 259 2.0 MB
Short description

Workshop Manual for Audi A4 and A4 Cabriolet — Auxiliary Heater (Edition 08.2004). Contains self-diagnosis procedures, fault tables, electrical and fuel system checks, final control tests, CO₂ exhaust adjustment and step-by-step removal/installation and repair procedures. Intended for professional workshop use.

199,00 UAH
Contents
Key sections:
  • 01 - Self-diagnosis, electrical checks
  • 1 Auxiliary heater self-diagnosis
  • 1.1 Technical data of self-diagnosis
  • 1.2 Function
  • 1.3 Fault recognition
  • 1.4 Guided fault-finding
  • 1.5 Technical data of self-diagnosis
  • 1.6 Test requirements for self-diagnosis
  • 1.7 Safety precautions
  • 2 Self-diagnosis procedure
  • 2.1 Connecting vehicle diagnostic VAS 5051A/K-wire adapter
  • 2.1.1 Control unit identification
Buy

Audi A4 / A4 Cabriolet (1.8T 4‑cyl turbo) — Motronic Injection & Ignition System Service Manual (Edition 01.2015)

Workshop Manual
Years: 2001 Manual in English Pages: 34 851.0 KB
Short description

Service manual for Audi A4 (2001‑) and A4 Cabriolet (2003‑) with 1.8L 4‑cylinder turbo engines. Covers Motronic fuel injection and ignition systems, diagnostic and maintenance procedures. Includes technical data, removal/installation steps and system checks.

199,00 UAH
Contents
Key sections:
  • 24 - Mixture preparation - injection
  • 1 Safety precautions and rules for cleanliness
  • 1.1 General notes on self-diagnosis
  • 1.2 Safety precautions when using testers and measuring instruments during a road test
  • 1.3 Rules for cleanliness and instructions for working on fuel system
  • 1.4 Checking vacuum system
  • 2 Injection system
  • 2.1 Technical data
  • 2.2 Overview of fitting locations - injection system
  • 3 Intake manifold
  • 3.1 Exploded view - intake manifold
  • 3.2 Removing and installing intake manifold
Buy

Audi A8 (2003) — Electrical System Workshop Manual (Edition 08.2014)

Workshop Manual
Years: 2003 Manual in English Pages: 369 9.1 MB
Short description

Comprehensive workshop manual for the Audi A8 (2003) electrical system — Edition 08.2014. Covers battery, alternator, starter, instrument cluster, wiper/washer systems, exterior/interior lighting and wiring repair procedures with step-by-step illustrations. Includes diagnostic and adjustment procedures and torque/data specifications.

199,00 UAH
Contents
Key sections:
  • 27 - Starter, current supply, CCS
  • 1 Contact corrosion
  • 2 Battery
  • 2.1 Battery - general notes
  • 2.2 Maintenance-free batteries
  • 2.3 Disconnecting and connecting battery
  • 2.4 Removing and installing battery
  • - Remove luggage compartment side trim (right-side)
  • - Connect battery charger for back-up power
  • - Detach earth and positive cables, central venting hose
  • - Remove battery retainer plate and lift battery out
  • - Installation notes, adaptation via Vehicle diagnostic tester
Buy

Audi Q4 e-tron (Type F4) - Self-study Programme SSP 685

Workshop Manual
Years: 2021 Manual in English Pages: 186 82.7 MB
Short description

Official Audi Service Training self‑study programme SSP 685 for the Audi Q4 e‑tron (Type F4). Covers body, power units, power transmission, running gear, electrics & electronics, high‑voltage system, thermal management, driver assist and infotainment. Intended for internal service training and technical familiarisation; not a workshop repair manual.

199,00 UAH
Contents
Key sections:
  • Introduction
  • - Introduction to Audi Q4 e-tron
  • - Dimensions
  • Body
  • - Body structure and materials
  • - Joining techniques
  • - Securing high-voltage battery and force progression
  • - Body assembly (doors, rear lid, panoramic sunroof)
  • - Dash panel and centre console
  • Power units
  • - Technical data: rear electric motor (VX90)
  • - Technical data: front electric motor (VX89)
Buy

Audi Q8 (2018) — Electrical System Workshop Manual (Edition 05.2019)

Workshop Manual
Years: 2018 Manual in English Pages: 645 14.8 MB
Short description

Workshop manual for the Audi Q8 (2018) — Electrical System. Includes technical data, safety notes and step‑by‑step repair procedures for battery/charging, starter/alternator, lighting, washer/wiper and wiring. Edition 05.2019.

199,00 UAH
Contents
Key sections:
  • 00 - Technical data
  • 1 Safety precautions
  • 1.1 Safety precautions when working on vehicles with start/stop system
  • 1.2 Safety precautions when using testers and measuring instruments during a road test
  • 1.3 Notes on use and safety for LED headlights and Audi laser lights
  • 2 Repair notes
  • 2.1 Rules for cleanliness
  • 2.2 General notes
  • 2.3 Contact corrosion
  • 2.4 ESD (electrostatic discharge) workplace
  • 2.5 Routing and attachment of lines and wiring
  • 2.6 Identification plates
Buy

Audi Servicing Manual — 7‑Speed Dual Clutch Transmission 0CJ / 0CL / 0CK / 0DN / 0DP / 0HL (Edition 05.2018)

Workshop Manual
Years: 2008–2019 Manual in English Pages: 128 11.1 MB
Short description

Service manual for the 7‑Speed dual‑clutch (DSG) transmissions 0CJ/0CL/0CK/0DN/0DP/0HL fitted to various Audi models. Includes repair information, clutch and gearbox disassembly/assembly, mechatronic and hydraulic system procedures, seals and differential work. Edition 05.2018.

199,00 UAH
Contents
Key sections:
  • 00 - General, Technical Data
  • 1 Repair Information
  • 1.1 General Repair Information
  • 1.2 Contact Corrosion
  • 1.3 ATF Pump, Deactivating and Draining the Hydraulic Pump Reservoir
  • 2 Rules for Cleanliness when Working on DSG® Transmission
  • 30 - Clutch
  • 1 Clutch
  • 1.1 Overview - Flywheel and Dual Clutch
  • 1.2 Flywheel, Removing and Installing
  • 1.3 Dual Clutch, Removing and Installing
  • 1.4 Input Shaft Seal, Replacing
Buy
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.

199,00 UAH
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
Buy

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.

199,00 UAH
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
Buy

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.

199,00 UAH
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
Buy
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email

Report

Harassment or bullying behavior
Contains mature or sensitive content
Contains misleading or false information
Contains abusive or derogatory content
Contains spam, fake content or potential malware

Block Member?

Please confirm you want to block this member.

You will no longer be able to:

  • See blocked member's posts
  • Mention this member in posts
  • Invite this member to groups
  • Message this member
  • Add this member as a connection

Please note: This action will also remove this member from your connections and send a report to the site admin. Please allow a few minutes for this process to complete.

Report

You have already reported this .