What are the best ways to identify electronic faults in a vehicle?

Visual observations are always the starting point. It can help you find the more obvious problems,but most of the time it takes more diagnosis to find the right problem. The use of all the information and tools at your disposal is always the best course of action.

Identifying electronic faults in a vehicle can be a challenging task, but there are several methods and tools available to help diagnose and troubleshoot electronic issues. Here are some of the best ways to identify electronic faults in a vehicle: 1) Onboard Diagnostics (OBD-II) Scanner 2) Multimeter 3) Visual Inspection ( check wear and tear in wiring) 4) Refer to the vehicle's wiring diagrams to understand the electrical system's layout. 5) Check Fuses 6) Actuator Testing 7) Check for Software Updates and professional assistance.

Everything in this is accurate from a technician point if view, one thing i come accross alot is corroded wiring, and best indicator is the loom tape with have a green/white discolouring to it showing signs of water ingress which is a good point to start at, also with the burning of wiring, it may not always be as simple as a black burnt crisp, but more like a slightly melted and disformed wiring insulation from high resistance which can be overlooked.

Using IoT, we can detect electronic faults in various engine types by examining the ECU board, checking sensor conditions and pressure. The most effective approach involves updating the system and improving the driver's capacity within the vehicle system, connecting all sensors to the ECU to signal power loss or battery backup issues.

In my experience starting any diagnosis with a thorough visual inspection is paramount. I have found a person can chase a problem down the perveribal RABBIT HOLE if they would have just kept it simple and checked the basics first.

This is great for a typical standard 12v system where you want to see load testing like a light bulb system (incadesent type) but one some new cars especially EV, standard voltage and resistance testing can be futile, so we have to use voltage drop testing instead or resistance line checking (continuity) as continuity doesn't always show how good the wire is, voltage drop test shows the difference between 2 points wich should be from supply and ground. Also with the likes of LEDs, we have to use oscilloscopes and diagnostic computers as its run by a duty cycle which typically is faster then the rate a multi meter can see, so for those in the trade or comming in the trade it is shifting and changing everyday.

I've come across that, when a wire is damaged but not broken, you can't see it with multimeter. Multimeter will show you the proper voltage, current, until you add a load to the end of line. As a load you can use a light bulb or an indicator (non LED).

Not every multimeter has the ability to show duty cycle, but duty cycle is more and more used in vehicles. So if you want to be good at your trade, you need to get a multimeter, that can read duty cycle (%).

Pin point testing is best! Or use a scope. Best way to find faults! If you can duplicate the problem helps too! Heating or cooling help too.

Most of the faults are covered in Diagnostics, A failure which leads to problem for the user will be covered mostly by Diagnostic trouble codes.

Not all electronics control units publish fault codes as DM1. But for those which does, it is important to assess what they are. For those which does not publish the fault codes as DM1, still publishes but not in J1939 format, in some user defined messages. You need to understand those before any troubleshooting and it may save lots of time.

Diagnostic Trouble Codes are only as good as the electrical properties present at the Input/Output pins of the controller. The hardware and algorithms cannot “see” anything else. DTCs make pass/fail decisions based on these interface terminal properties. They cannot determine that a sensor is bad, only that a sensor “looks bad” based on its view of the electrical values at the pins. They cannot determine flow is insufficient, only that the terminal values “appear insufficient” electrically. Great starting point. Then it’s time for schematics, diagnostic specifications, instruments, meters, and sometimes scopes, to identify which part of the “real world” is the problem.

I think scan tools are effective ways to detect faults in Automobiles, expert knowledge is also needed to successfully address faults detected using the scan tool, for example, a sensor might be detected as a fault, however, this might be caused by insufficient signals getting to and from said sensor so I believe that in as much as scan tools are effective in detecting electronic faults, other tools like oscilloscopes and Multimeter also needs to be employed for effective diagnosis which is why domain expertise is very important. Lastly, scan tools may not detect some electronics faults which is where the domain and technical expertise comes in play.

Since the electronic fault is not defined, I would always start with a diagnosis first and investigation on the DTCs observed. If there are no DTCs then I expect that the fault is observed by driver, so I'd continue with a multimeter (U/I check) and logic probe for communication check.

Agreed. Whilst multimeter’s are ok a scope can identify a bus fault a lot better. Had an intermittent Flexray fault on a Hybrid BMW and this was the only way I could find it. Understanding what the scope pattern should look like is also a must, so you can quickly see if a bus pattern is ok or not. Bus faults can cause random and complex faults and using a scope can save you a lot of stress and time!

Not only are they good at fault finding, but they are also good at data finding, and this might confuse some people but with Audi if you use ODIS oscilloscope you can set it to log a report overnight for example to see a battery drain or what the ultrasonic sensors are doing, to see how a duty cycle is ran when LEDs are turned on or off, to then compare to what the manufactuer releases or their technical department requests to see it.

The use of a logic tool is one of many ways to determine if a circuit is bad or if the part is bad. I have used many different ways to diagnose problems.

In my experience, to identify an electrical fault in a vehicle a top to bottom approach is helpful. Beginning with a fishbone analysis which consists of listing down possible root causes. Then trying to understand under which circumstances the issue behavior occurs, e.g. while starting the ECU, during shutdown or any other time during runtime. Based on the communication or diagnostics logs from the vehicle, issue reproduction can be tried to further debug the fault. If the circumstances of issue appearance are unknown or ambiguous, finding a pattern in the vehicle logs can be useful to get more insights. If the issue is reproducible only on a certain test bench environment, comparison with the development test bench can be helpful as well.

I suppose all the above tests can be found very useful but if we can get to the fault methodical with why-why analogy from output to input or vice versa then me can surely optimise the time and efforts to locate the fault. So best case can be that we would just need one or two tests like multimeter or Oscilloscope and we should able to find the root cause.

Looking through all of the other great suggestions, there is one item missing: background. When did this electrical fault start? How do we duplicate this electrical fault? What conditions are present when it occurs? Having a great meter, scope, short finder, service manual, or scan tool help, but knowing that the concern occurs when it is "_____" while doing "_____" if you use "_____" is just as important. To answer the question posed, a thorough explanation of the who, what, when, where, why, how of re-creation and origination of the incident is the most useful tool to conquer electrical faults.

Tracing and logging tools and infrastructure (e.g., DLT tracing) is a key element of the EE development of a vehicle. New model development is unthinkable without well-designed infrastructure for collecting data from vehicles. By "infrastructure" I mean: (1)in-car EE devices designed to- and capable of- storing and emitting diagnostic data, (2)enough bandwidth to transmit this data without sacrificing core vehicle functions and (3)IT infrastructure like data centers to collect and record this data. Special care is to be taken for the parts of the infrastructure that remains active after the vehicle launch - to still be able to find and root-cause sporadic issues. Privacy and cyber-security is then the next big concern for these systems.

Identifying electronic faults in vehicles often involves using diagnostic tools like OBD scanners to read error codes, inspecting wiring for damage or loose connections, checking fuses, and testing components like sensors or modules for proper function. Expertise in interpreting diagnostic data and electrical schematics is crucial.