What a vehicle diagnostic test can tell you

What could be better than cruising down the highway and enjoying the scenery? But out of nowhere, the dreaded ‘check engine’ light appears. What a nightmare!

As technology continues to improve, car components have become computerised. These significant advances are beneficial to both car owners and auto technicians alike.

Most modern cars now have automatic transmissions, ignition systems, and fuel injection systems. They are all controlled by computers.

Each of these computers sends data from dozens of sensors located throughout the car.

What happens when a sensor detects a problem? It turns on your check engine light, to notify you something is wrong.

What is a Car Diagnostic Test?

A car diagnostic test uses specialist software and vehicle diagnostics tools. The test makes it easy to find the exact problem with a car’s engine. This is possible because of the microchips. As well as the built-in processors and sensors in the vehicle.

A vehicle diagnostics test saves both time and money. A problem can be determined by this test. Without having to spend hours manually pulling apart components to detect a fault. Luckily those days are a thing of the past.

Car mechanic working on the undercarriage of a lifted vehicle in a workshop

What does a diagnostic test do for a vehicle?

A diagnostic test checks many different components of a car. These include:

  • The engine
  • Transmission
  • Brakes
  • Exhaust system

A diagnostic test is also able to find any performance issues with:

  • The fuel injector
  • Ignition coils
  • Airflow and coolant
  • Throttle

There are four main things a car diagnostic test will be able to check with your vehicle. They include:

Car mechanic working on the undercarriage of a lifted vehicle in a workshop

1. What is the emissions level of your vehicle?

The emissions level determines how environmentally friendly your vehicle is for the environment. The test will determine the health of the exhaust system, and also if your vehicle requires a tune-up.

2. Does the PCM (Powertrain Control Module) have any faults?

A light flashing on the dashboard will show any faults with the PCM. If a fault is detected, it means that it’s possible there may be a range of different problems. The good news is, they can be fixed while they are still small. Rather than becoming expensive as they get worse over time.

3. What is the idle speed stress?

Your air control valve may experience problems if the engine of your car runs either too slow. Or too fast, or it is stalling. Also, if there is a leak in the engine vacuum, it will have to work overtime to be able to perform.

4. Does the transmission have any problems?

A diagnostic test identifies any symptoms that may take a while to notice. What if you do detect any small problems with the transmission early? Well, it can prevent you from needing to spend a small fortune for a transmission repair in the future.

Why are regular diagnostic tests important?

Like an annual checkup from your Doctor, a regular diagnostic test is beneficial for your car. It can help to detect any problems early. So that you can fix them before they become worse and need expensive repairs. Or even worse, leave you stranded in the middle of nowhere due to your car breaking down.

A diagnostic test doesn’t only detect the issue. It also lets you know how long it has been there for key/start cycles, drive cycles, and in real time. It will also tell you how many times the error has happened.

This is crucial for determining if it was a one-off problem, or it’s something that’s been getting worse over an extended period.

Diagnostic Test Myths

There is a myth that diagnostic tests can pinpoint the exact problem which caused the check engine light by using code-reading tools? Unfortunately not.

Instead, the code only says which component or engine parameter that has a problem. It doesn’t reveal the cause of the problem or any detail.

It’s then up to the auto electrician to use their expertise and experience to be able to diagnose the problem.

This makes it critical to use an experienced auto electrician you can trust.

Car mechanic troubleshooting a car issue beneath a lifted vehicle in a professional repair shop.

How much does it cost to run a diagnostic test on a vehicle?

It depends on the location. But generally, you should expect to pay anywhere between $60-100 for a car diagnostic test.

At Sandgate Auto Electrics, we offer a diagnostic test for $70 which includes an OBD2 health check. This involves thoroughly checking the onboard EMS (engine management system) to detect any fault codes and analyse data.

How long does a diagnostic test for a vehicle take?

Vehicle diagnostics generally takes less than an hour to complete. It can end up saving your auto mechanic a significant amount of time. Instead of trying to troubleshoot and detect what the problem is manually.

It also allows you to save money. Detecting problems early means they can be fixed quickly. Before they turn into more expensive repairs once the problem has gotten a lot worse.

Car mechanic servicing a vehicle with the engine compartment open in a workshop.

How often should you have a diagnostics test?

It’s best to have a car diagnostic test anytime you hear something unusual. Or your car feels or handles differently. A qualified auto electrician can detect the problem quickly.

Did you know that it’s possible for errors to occur in your vehicle which won’t trigger the check engine light? These are usually minor problems. But, what if they are left without being repaired for a long time? Then they can potentially turn from a minor problem to a major one.

It’s suggested to undergo vehicle diagnostics at least once per year.

Diagnostic Test for a Used Car

If you are looking to buy a used car, then it’s recommended to have a diagnostic test performed before you commit to buy. Private sellers and car dealerships should agree to have a diagnostic test performed. If they don’t, then that’s a major red flag that perhaps there may be something majorly wrong with the vehicle.

Do you have a problem with your check engine light? Or do you want the peace of mind of a regular car diagnostic test? Sandgate Auto Electrics are experienced and reliable auto electricians. Contact us today to book your $70 vehicle diagnostics test. Call (07) 3269 3158 or contact us online.