The best tool for diagnosing sensor failures
The sensors that monitor the fuel, electronic and mechanical components that power today's vehicles are prime candidates for most of the problems that drive a phone call from a customer to an ASE certified mechanic. Whether the sensor is broken, has an electrical connection problem, or is dirty, most mechanics will agree that sensor failures make up the majority of their diagnostic inspections and repairs. It is also a statement of fact that a sensor problem can be extremely difficult to diagnose with standard test equipment. One of the best tools that mechanics use to diagnose sensor failures and pinpoint the exact location of the failure is an automotive oscilloscope.
What is an automotive oscilloscope?
In general, an oscilloscope is an electrical machine that displays the electronic signals that are created through an electrical circuit. Unlike a standard voltmeter, an automotive oscilloscope is typically an LCD screen divided into equally sized squares that display deviations in output signals created by faulty sensors, secondary ignition circuits, starter motor systems, intake manifold pressure, and charging currents from car battery.
Today's mechanics use four main types of automotive oscilloscopes to diagnose sensor problems, including:
- Analog oscilloscope: This old type of monitoring device has a cathode ray tube screen that shows higher frequencies; however, are less common in today's automotive world.
- Digital storage oscilloscope: This type of endoscope is used with a PC, allowing the mechanic to display the electrical current, save the image, print it, and check it for individual problems.
- Multichannel oscilloscopes: This type of digital oscilloscope can be divided into three different output and input signals.
- Universal oscilloscope: A general purpose oscilloscope is commonly used in the automotive industry to diagnose problems with sensors, fuel injectors, ABS systems, fuel pump problems, compression checks, and more.
How does an automotive oscilloscope work?
An automotive oscilloscope is designed to find inconsistencies that are very difficult to find with the normal diagnostic tools that most mechanics use. There is an exact process that mechanics use to wire up and use an oscilloscope to find problems with a sensor:
- If necessary, connect the oscilloscope to a laptop or desktop PC.
- Connect the oscilloscope to the sensor or injector to be tested. It is important that the oscilloscope probes do not come into contact with other metal components and that it is grounded before turning on the oscilloscope.
- Start the car engine to display the electric tracks. Although the oscilloscope is connected to only one of the sensors or injectors, the electrical traces of all sensors or injectors will be displayed on the screen. This allows the mechanic to find an inconsistency in an individual sensor or group of sensors, which will lead to the problem being located and the appropriate repair to be carried out.
- The mechanic can view the electrical signals in real time and measure the time of each electronic actuation. This is important when trying to diagnose a problem with any sensor; as it can misfire slightly, which is often overlooked by most standard diagnostic tools.
The ability to perform a real-time diagnostic inspection of a vehicle with an oscilloscope gives any mechanic an advantage over those who do not use this type of equipment. Most importantly, it helps mechanics speed up the repair of faulty sensors, allowing them to do more work without wasting valuable time or resources.
If you are a certified mechanic and interested in working with AvtoTachki, please apply online for the opportunity to become a mobile mechanic.
