Find What’s Wrong With Your Car.

Trouble codes, warning lights, symptoms and troubleshooting guides for everyday car problems.

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You don’t need to know the name of the part. Start with what you can see, hear, smell or feel — we’ll work back to the likely cause.

A warning light is onDashboard lights explained I hear a noiseClicking, grinding, squealing I smell somethingBurning, sweet, fuel, mould Something is leakingIdentify it by colour The car shakesAt idle, speed or braking It won’t startNo crank, clicking, cranks only It has no powerHesitation, jerking, limp mode Smoke from the exhaustWhite, blue, black or grey It’s overheatingCoolant, fans, thermostat Braking feels wrongSqueal, grind, pull, soft pedal Electrical gremlinsBattery, alternator, drains The AC isn’t coldWarm air, weak flow, smells

Popular Trouble Codes

All trouble codes ›

Plugged in a scanner and got a code? Here’s what it actually means, how serious it is and what usually fixes it.

U0121 Code: Lost Communication With ABS Control Module

This completes the network-fault family alongside U0100 and U0101 — the same category of problem, this time affecting the module responsible for…
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P0463 Code: Fuel Level Sensor Circuit High Input

This code and a dead fuel gauge are usually two symptoms of the exact same failed part — the sending unit inside…
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P0456 Code: EVAP System Very Small Leak Detected

This completes a three-tier leak-size hierarchy — very small, small, and gross — and it’s the one most often caused by nothing…
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P0303 Code: Cylinder 3 Misfire Detected

With P0301 and P0304 already covered, P0303 completes the most commonly searched trio of single-cylinder misfire codes — the diagnostic approach is…
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P0201 Code: Injector Circuit Malfunction – Cylinder 1

An injector circuit fault stops fuel delivery to one cylinder entirely — a more absolute problem than the partial misfire causes covered…
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P0230 Code: Fuel Pump Primary Circuit Malfunction

This is an electrical circuit fault, not a description of the pump’s mechanical condition — a healthy pump with a bad relay…
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Dashboard Warning Lights

All warning lights ›

Amber means investigate soon. Red means stop safely and check now. Tap a light to see what triggers it and whether you can keep driving.

Check Engine ABS Battery Oil Pressure Temperature Airbag / SRS TPMS Brake Traction Control

Common Car Problems

All problems ›

Transmission Whines in Reverse Only: Causes

A whine or hum specifically while backing up — with reverse otherwise engaging and working completely normally — is a distinct, usually…
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Car Smells Like Exhaust Inside the Cabin: What to Do

An exhaust smell inside the cabin means exhaust gas — potentially including carbon monoxide — is reaching the space you’re breathing in.…
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Exhaust Ticking or Popping Noise at Startup: Causes

A ticking or popping sound from the engine bay that’s loudest right after startup and fades as the engine warms is a…
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Grinding Noise When Turning the Steering Wheel at Low Speed

A grinding sound that only shows up while turning the wheel at low speed — pulling into a parking space, making a…
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AC Blows Cold on One Side Only (Driver vs Passenger)

On dual-zone systems, a temperature difference between sides is usually a mechanical door problem, not a sign the AC system itself is…
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Car Won’t Go Into Park: Causes

Park uses a completely different mechanical system from every other gear — a dedicated pawl that physically locks the output shaft, which…
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Browse by System

EngineMisfires, rough idle, oil use TransmissionSlipping, harsh shifts, shudder Electrical & BatteryBattery, alternator, starter BrakesPads, rotors, ABS, pedal feel Steering & SuspensionClunks, pulling, tyre wear Cooling SystemOverheating, leaks, thermostats Air ConditioningWarm air, leaks, compressors MaintenanceFluids, filters, intervals

Browse by Car Brand

All brands ›

Every make has its known weak points. Find the faults, codes and warning lights that owners of your car report most.

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Latest Troubleshooting Guides

Toyota Tacoma Common Problems

The Tacoma’s frame corrosion issue is one of the rare cases on this site backed by an actual manufacturer buyback and frame…
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Honda CR-V Common Problems

The CR-V’s most significant documented issue is specific to the 1.5L turbo engine and a particular driving pattern — short, cold trips…
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Ford F-150 Common Problems

The F-150’s most distinctive documented issue is specific to EcoBoost engines and a particular combination of weather conditions — here’s what it…
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How to Tell If Your Cabin Air Filter Needs Replacing

A clogged cabin air filter doesn’t announce itself with a warning light — it shows up as gradual changes to airflow and…
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How to Jump Start a Car With a Portable Jump Starter

A portable jump starter removes the need for a second running vehicle entirely, but the same core safety rules from cable-to-cable jump…
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How to Read a Car Battery Date Code

Every car battery has a small sticker or stamp showing when it was manufactured — decoding it tells you how close it…
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How to Check Coolant Level Safely

Checking coolant is simple, but doing it safely depends entirely on one rule: never open a pressurized, hot cooling system. Here’s exactly…
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Synthetic vs Conventional Oil: Which Should You Use?

Neither oil type is objectively better — the right choice depends on your engine’s requirements, your climate, and how much you value…
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A quick word on safety. Car Fault Finder helps you understand what your car is telling you. Brakes, steering, fuel, airbags and high-voltage hybrid or EV systems can injure or kill if they are worked on incorrectly. If a job is beyond your tools, your workspace or your confidence, hand it to a qualified mechanic.