Fault codes and DTC diagnosis
Move from P/U codes and manufacturer-specific DTCs to symptoms, data and measurement.
AutoAtlas Automotive Technical Knowledge Center
AutoAtlas brings model, engine, transmission, diagnostic trouble code and measurement-based technical knowledge together for cars, motorcycles, commercial vehicles, heavy vehicles and machinery.
KNOWLEDGE CENTERS
AutoAtlas technical knowledge hubs
A direct map of the site’s primary topics for users and search engines.
01Source-backed technical knowledgeClaims, measurements and application context stay distinct.
02Diagnosis firstMeasurement chain before parts replacement.
03Vehicle identityBrand, model, engine and transmission stay connected.
04TR + ENVerified language surfaces, no copy-paste location pages.
VEHICLE CLASSES
Move from vehicle type to the right knowledge
Every model is connected to its vehicle class, brand and dedicated model page.
2,011
Passenger Cars
Passenger, performance and personal mobility vehicles.
162 brands →92Light Commercial Vehicles
Vans, combivans, minibuses and chassis cabs.
25 brands →263Trucks
From light distribution to heavy vocational trucks.
23 brands →138Buses and Coaches
Urban, touring, school and intercity passenger vehicles.
18 brands →215Agricultural Machinery
Tractors, harvesters and field machinery.
12 brands →347Construction Machinery
Excavators, loaders, dozers, graders, cranes and forklifts.
10 brands →199Motorcycles
Scooters, touring, enduro, supersport and electric motorcycles.
13 brands →KNOWLEDGE DOORS
All categories →Enter the topic directly
Models
Brands, families, generations and bodies.
3,265 records→Engines
Engine families, codes, applications and service context.
485 records→Transmissions
Manual, automatic, DCT, CVT and driveline systems.
202 records→Fault Codes
Symptoms, causes, live data, measurement and verification.
647 records→Deep Guides
Diagnostics, electronics, mechanics and engineering files.
67 records→Technologies
How systems work and how they connect to diagnosis.
122 records→Brands
Categorized model directory for every brand.
183 records→Parts and Systems
Component role, failure chain and test approach.
24 records→BRAND DIRECTORY
All brands →Brands with the broadest model network
ADVANCED DIAGNOSTICS AND ENGINEERING
Measurement-based technical references for engine, driveline and DTC diagnosis
Variant identity, live data, oscilloscope waveforms, mechanical verification and post-repair testing are evaluated in one diagnostic chain.
Model
Volkswagen Golf
Volkswagen Golf model-family index covering production span, chassis/generation codes, body styles and representative powertrains.
Open technical analysis→
ModelVolkswagen Golf R: generation, EA888, DSG and 4MOTION inspection file
The Golf R name spans R32 through modern EA888/DSG models with different 4MOTION generations. Inspection must combine generation, engine, transmission, AWD and modification history.
Open technical analysis→
EngineVolkswagen 1.4 TSI: EA111/EA211 variant and diagnostic file
The 1.4 TSI name covers chain-driven EA111, belt-driven EA211, ACT and different turbo/fuel arrangements. Parts, fluids and timing decisions require the exact engine code.
Open technical analysis→
EngineRenault K9K 1.5 dCi: sub-code, injection, turbo and DPF diagnostic file
K9K is not one engine. The sub-code changes injector supplier, output, turbo, DPF/SCR, lubrication and vehicle application.
Open technical analysis→
EngineToyota 1.6 Valvematic 1ZR-FAE: actuator, learning and air-management file
Valvematic manages air by continuously varying intake-valve lift and works with VVT-i. Idle and response diagnosis must separate actuator, learning, oil and conventional air leaks.
Open technical analysis→
EngineBMW N47: timing-chain, fuel, EGR/DPF and turbo diagnostic file
N47 is a 2.0 diesel family with several sub-codes and outputs. A timing-chain noise claim requires correlation, oil, wear and other rotating components to be separated.
Open technical analysis→
EngineMercedes-Benz M274: timing, fuel, boost and thermal-management file
For the M274 family, sub-code, vehicle installation and calibration are the starting point for timing correlation, direct injection, turbo control and cooling diagnosis.
Open technical analysis→
EngineStellantis/PSA 1.5 BlueHDi DV5: chain, SCR, DPF and fuel file
In the DV5 family, sub-code, production period and emissions hardware underpin camshaft-chain, fuel, turbo and SCR diagnosis. Stellantis special coverage for certain earlier production makes VIN checking critical.
Open technical analysis→
EngineStellantis/PSA EB PureTech: oil consumption, wet-belt and turbo file
Official coverage exists for oil consumption and premature timing-belt degradation on previous 1.0/1.2 PureTech generations. Diagnosis depends on engine code, production, belt revision and oil-system evidence.
Open technical analysis→
Fault CodeP0420 · Catalyst System Efficiency Below Threshold Bank 1
P0420: Catalyst System Efficiency Below Threshold Bank 1. The dossier separates circuit logic, freeze-frame context, live data, meter/scope tests and repair verification by diagnostic system.
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Fault CodeP0300 · Random/Multiple Cylinder Misfire Detected
P0300: Random/Multiple Cylinder Misfire Detected. The dossier separates circuit logic, freeze-frame context, live data, meter/scope tests and repair verification by diagnostic system.
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Fault CodeU0100 · Lost Communication With ECM/PCM A
U0100: Lost Communication With ECM/PCM A. The dossier separates circuit logic, freeze-frame context, live data, meter/scope tests and repair verification by diagnostic system.
Open technical analysis→
SERVICE & OWNERSHIP DECISIONS
All service guides →Choose the right test before the expensive decision
High-intent guides connecting fault codes, measurements, service planning and related technical records.
Check Engine Light: What Determines Diagnostic Cost?A structured service plan that connects DTCs, freeze-frame, live data, circuit checks and mechanical evidence before parts are replaced.P0420 and Catalyst Diagnosis Before ReplacementA measured approach to oxygen sensors, exhaust leaks, fuel trims, misfire and catalyst efficiency before a costly converter decision.Automatic Transmission and Mechatronics: Proving the Repair PathA diagnostic framework for DCT, conventional automatic and CVT faults using fluid, pressure, adaptation and electrical evidence.EV Battery Health: SOH Is More Than One NumberAn EV battery assessment covering usable energy, cell/module delta, temperature, fast charging and isolation context.ADAS Calibration After Glass, Alignment, Suspension or Collision RepairA planning guide for camera/radar calibration with geometry, tire pressure, ride height, steering-angle and OEM procedure controls.Used-Car Technical Inspection: DTC, Chassis, Powertrain and ADASA pre-purchase framework combining full-module scan, live data, powertrain, chassis, SRS, ADAS and EV/HV checks.
GLOBAL TECHNICAL DISCOVERY
From fault codes and symptoms to vehicle identity
Technical path
DTC, Fault Codes & OBD-II Diagnostic Center
Research DTC codes, fault codes and OBD-II codes through meanings, symptoms, freeze-frame data, live data, circuit checks and repair verification.
Technical pathVehicle Symptom Diagnostics
Start from the symptom, not a guessed part: hesitation, loss of power, no-start, harsh shifts, overheating and charging faults connected to measurable diagnostic paths.
Technical pathCar Brand, Model & Variant Technical Atlas
Explore car and vehicle brand-model-variant identity together with engines, transmissions, generations, markets and technical records.
Technical pathEngine & Transmission Common Problems
Research engine codes, engine families, transmission codes and driveline systems through symptoms, DTCs, maintenance context and repair evidence.
Technical pathUsed-Car Technical Inspection Center
Combine DTC scans, live data, powertrain, chassis, SRS, ADAS and EV/HV checks before buying a used car.
Technical pathEV Battery & Charging Diagnostics
Explore BMS, battery health, cell balance, isolation, onboard charging, DC fast charging and thermal management through safe diagnostic workflows.
Technical pathHeavy-Duty J1939, SPN & FMI Diagnostics
Connect truck and heavy-duty SPN/FMI, ECU source addresses, CAN/J1939, engine, emissions and braking systems to technical records.
Move from diagnosis to a service decision
After confirming DTC, symptom and vehicle identity, continue through engine/transmission, service, used-vehicle inspection and ownership guides so the same fault can be cross-checked from multiple systems.
FROM FIELD TO WORKSHOP
Technical entry paths for workshops, agriculture, heavy equipment and fleets
Workshop, Technician & Service Technical Center
Diagnostic paths for independent workshops, dealer technicians, auto electricians, diesel specialists, transmission shops and inspection professionals.
Tractor & Agricultural Machinery Diagnostic Center
Engine, transmission, hydraulics, PTO, hitch, CAN/J1939, DTC and electrical diagnostic paths for farmers and agricultural workshops.
Construction & Heavy Equipment Diagnostic Center
Technical discovery for excavators, loaders, dozers, forklifts, cranes and site equipment: engine, hydraulics, CAN/J1939, SPN/FMI, emissions and electrical faults.
Fleet & Public Works Maintenance Technical Center
Diagnostic and maintenance paths for municipal fleets, public agencies, workshops and mixed fleets of trucks, buses, service vehicles, heavy equipment and tractors.
OWNERSHIP INTELLIGENCE
Reliability, cost planning and your garage
Vehicle Reliability & Common Problems Center
Research model, engine and transmission issues through DTCs, recalls, technical records and maintenance context. No complaint rate is invented without verified data.
Repair & Maintenance Cost Planner
Calculate parts, labor, tax and contingency using your own real values; the tool does not invent market prices.
My Garage
A lightweight browser-local garage for vehicle, maintenance and DTC notes.
OWNERSHIP & COST
Open ownership center →Move from fault page to budget decision
Compare maintenance, used-car, EV/hybrid and repair quotes with technical evidence.
ALL MACHINES + DEEP DIAGNOSTICS
Go beyond cars and explore the whole machine world
Motorcycles, trucks, tractors, construction machines, marine engines and unusual fault phenomena.
TECHNICAL DATA CENTER
Engine, transmission and heavy-duty diagnostic data expanded
220 engine families, 102 driveline families and 924 J1939 SPN/FMI references plus deeper measurement and decision chains on existing DTC/model pages.
TECHNICAL KNOWLEDGE CENTER
Technical knowledge by vehicle class and system
Vehicle classes, systems, DTCs and model pages are connected through measurement, evidence and technical identity verification.
GLOBAL MODEL ATLAS
2,000+ real model/variant records connected
1883 indexable model families and 2108 market/variant rows with generation and powertrain differences preserved.
MODEL AND TECHNICAL TOPIC ATLAS
Connected model, variant and technical topics
Model variants and deep technical topics are presented with identity, diagnosis, measurement and related-content links.
TECHNICAL VARIANT DOSSIERS
Open technical center →Three distinct technical intents per variant
1,915 variants deepened with powertrain/driveline, electrical/network and used/service verification dossiers.
TECHNICAL COVERAGE
Expanded technical content network
Four new search intents per variant and four new evidence/decision perspectives per deep technical topic, connected to the existing knowledge graph.
BALANCED TECHNICAL COVERAGE
Open technical coverage →Technical depth across every vehicle class
Passenger cars, heavy vehicles, agriculture, construction equipment, motorcycles and other classes are expanded with balanced diagnostic, powertrain, electronics and service context.
TECHNICAL COVERAGE
Open technical network →System-wide technical knowledge network
Vehicle class, model, engine, transmission, DTC, electronics and service intent are connected through real technical records and measurement-led guides.
FROM SEARCH INTENT TO TECHNICAL ANSWER
Turn the phrase you searched into a measurable diagnostic path
Fault-code, freeze-frame, engine, transmission, CAN/J1939, tractor and equipment searches lead to real technical hubs rather than thin keyword pages.
Engine, transmission and vehicle identity
Research engine code, transmission family, generation, variant and application context together.
Live data and measurement
Connect freeze-frame, OBD live data, sensor circuits, CAN/J1939 and scope testing to the diagnostic chain.
Heavy duty, agriculture and equipment
Enter truck, bus, tractor and equipment diagnostics for electronics, aftertreatment, PTO and hydraulics.
DEEP TECHNICAL KNOWLEDGE
Turn high-demand technical questions into measurable workflows
Freeze-Frame Data: How to Read the Fault Snapshot
A practical guide to interpreting OBD/DTC freeze-frame data with rpm, load, speed, temperature, voltage and event context.
Open guide →How to Read OBD Live Data: PID and Sensor Diagnostics
How to select useful PIDs, compare commanded and actual values, assess rationality and reproduce fault conditions.
Open guide →CAN Bus Diagnostics: CAN-H, CAN-L and U-Code Faults
A structured approach to CAN faults covering power/ground, physical layer, termination, topology, gateways and module dropouts.
Open guide →J1939 SPN/FMI Guide for Heavy-Duty Diagnostics
A practical guide to J1939, SPN/FMI, source addresses and measurement-led diagnosis for heavy-duty vehicles and equipment.
Open guide →DPF, EGR and SCR Diagnostics: Pressure, NOx and Regeneration
How to evaluate DPF loading, differential pressure, EGT, EGR, SCR/DEF, NOx sensors and regeneration conditions together.
Open guide →Transmission and Mechatronics Diagnostics: TCM, Solenoids, Pressure and Ratio
A diagnostic framework for automatic, DCT and CVT systems using speed, ratio, pressure, solenoid, TCM and temperature data.
Open guide →Sensor Circuit Diagnostics: Reference, Ground and Signal Testing
How to diagnose automotive sensor circuits using reference/supply, ground, signal, rationality, voltage drop and oscilloscope testing.
Open guide →How to Find an Engine Code and Match the Correct Engine Family
How to verify an engine code using VIN/build data, labels, ECU identity, engine markings and manufacturer catalog information.
Open guide →FROM SYMPTOM TO DIAGNOSIS
High-demand symptoms drivers actually search for
Symptom → data → measurement → root-cause, not guessed parts.
Engine Cranks but Will Not Start: Systematic Diagnostic Guide
A measurement-led path for crank-no-start faults covering fuel, ignition, synchronization, compression, immobilizer and ECU data.
Open diagnostic guide →Engine Misfire and Jerking Diagnostics: Ignition, Fuel and Compression
Separate ignition, injector, fuel-trim, air-leak and compression causes using cylinder contribution and physical evidence.
Open diagnostic guide →Loss of Power and Limp-Mode Diagnostics
Diagnose loss of power using boost, air/fuel, rail pressure, aftertreatment, sensor rationality and ECU torque-limitation evidence.
Open diagnostic guide →Turbo Underboost and Overboost Diagnostics
Separate boost leaks, VGT/wastegate control, vacuum/electric actuators and exhaust restriction using target-versus-actual boost data.
Open diagnostic guide →Fuel Rail Pressure Diagnostics: Low/High Target-vs-Actual Pressure
Separate low-side supply, high-pressure pump, regulation, sensor and injector leakage in common-rail/direct-injection systems.
Open diagnostic guide →Engine Overheating Diagnostics: Cooling-System Test Path
A structured path for real temperature, fan command, thermostat, pump, flow, pressure, leaks and combustion-gas causes.
Open diagnostic guide →Battery, Charging and Parasitic-Drain Diagnostics
Diagnose weak batteries, charging systems, start-stop behavior, voltage drop, sleep current and module wake faults.
Open diagnostic guide →Harsh Shift, Slip and Delayed Engagement Diagnostics
Separate identity, fluid temperature, input/output speed, ratio, solenoid, pressure, adaptation and mechanical response in shift faults.
Open diagnostic guide →ABS/ESP Warning Diagnostics: Wheel-Speed and Brake Electronics
Diagnose ABS/ESP faults using wheel-speed sensors, tone rings, power, CAN, steering/yaw data and hydraulic-module context.
Open diagnostic guide →Blue, Black or White Exhaust Smoke: Diagnostic Guide
Interpret exhaust-smoke color with oil consumption, excess fuel, low air/boost, coolant, regeneration and operating temperature.
Open diagnostic guide →DPF Regeneration, SCR/DEF and Derate Diagnostics
Connect DPF load, differential pressure, EGT, NOx, DEF dosing, regeneration enables and derate in one diagnostic workflow.
Open diagnostic guide →ADAS Radar/Camera Warning: Diagnostics Before Calibration
Separate power, communication, field of view, mounting, chassis geometry, DTCs and calibration prerequisites in ADAS warnings.
Open diagnostic guide →REAL ANSWER CENTERS
Go directly to capacities, maintenance and measurements
Find sourced model-specific values in direct question-and-answer form, then continue to related models and diagnostic layers.
VEHICLE → BRAND → MODEL / VARIANT
Select a sourced technical model directly
No empty options: this selector contains only model and variant records backed by physical technical data.
605filled model/variants21 manufacturers · 11 vehicle groups
Coverage includes passenger cars/SUVs, light commercial vehicles, trucks, buses, construction machinery, tractors/agriculture, forklifts/industrial vehicles, motorcycles, ATV/UTV, marine and generator/stationary-engine records.
CaterpillarCaterpillar 330 GC OEM published configuration
18 sourced numeric technical fields
PolarisPolaris RZR XP 4 1000 Current specification18 sourced numeric technical fields
John DeereJohn Deere 8R 490 Current 8R17 sourced numeric technical fields
VolvoVolvo 9700 12.4 m / D13K 42016 sourced numeric technical fields
VolvoVolvo 9700 12.4 m / D13K 46016 sourced numeric technical fields
VolvoVolvo 9700 12.4 m / D13K 50016 sourced numeric technical fields