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By-pass fuses, I see them practically on all vehicles that have gotten one electrical issue or the other, infact is a culture done with confidence. I feel obliged to bring it here for discussion; is it just a normal thing or something that could later lead to costly repairs.

Please let's share our views as am aware vehicles from 2010 up are more complex in terms of electronics.

By-pass fuses, I see them practically on all vehicles that have gotten one electrical issue or the other, infact is a culture done with confidence. I feel obliged to bring it here for discussion; is it just a normal thing or something that could later lead to costly repairs.

Please let's share our views as am aware vehicles from 2010 up are more complex in terms of electronics.

is this a serious issue? The answer is absolutely "YES" it is always the secondary result of a serious electrical issue in your vehicle.

WHY DO FUSE GET SNAPPED?
Automobile like other critical equipment has several safety features and the fuse is one of them. If there is a current short either to ground or power, the fuse been a current limiting device will have to protect the circuit.

The protection mechanism ensure that when current above the rated fuse current, start flowing through the circuit over a given time period, the fuse should break the circuit.

WHAT ARE THE IMPLICATIONS OF REWIRING A BLOWN FUSE?
(1) It will lead to excess flow of current into the circuit where the safety feature has been compromised.
(2) It will lead to insulation breakdown of other adjacent wires, evidently resulting in other fuses been blown.
(3) Other circuits/components will be staved of current, thereby compounding the electrical faults in the vehicle overtime.
(4) Fire may result at the point where the short is occuring, due to heat build up.

WHY SNAPPED FUSE REWIRING PERSIST AMONG NIGERIA AUTO MECHANICS AND ELECTRICIANS?

(1) EDUCATION/TRAINING: understanding of basic electrical principles is critical when working on modern automobiles. This involves understanding the relationship amongst Current(I), Voltage (V) and Resistance (R).

(2) ELECTRICAL DIAGRAM: Knowing how to read electrical diagram is fundamental to circuit fault tracing.

(3) PROFICIENCY IN THE USE OF DIGITAL MULTIMETER: While most workmen are comfortable with the use of tools, most auto electricians/mechanics thread the thought of taking measurements.

In my next post, I will highlight why the Toyota vehicles, especially the older ones from 2008 down are more resilient to rewired blown fuse.

Fixing modern cars is now a mix of science and art, 70% science and 30% art. So in this forum we are going to be looking at both as we present DIAGNOSTIC TIPS & GUILD

P0300 is an obd2 generic code that basically tells you multiple cylinders are missing fire at the same time and at different time. Sometimes some cylinders are specifically mentioned. When your engine shakes, seems to loose power while accelerating, misfiring is most times the underlying issue.

HOW TO DIAGNOSE ENGINE MISFIRING
Most mechanics apply the art which is to fix not to diagnosing. Those with scanner scanned and look up the code, soon they drop it for the fix. Let's know look at the ART and the SCIENCE and a real world case.

The ART
The ART of fixing engine issue is to unplug the coil and see which really affected the engine and which did not, change coil, plugs, watch injectors and possibly replace fuel pump. These are based on experience not any scientific calculations.

The SCIENCE
Ask questions (still art), plug scanner, retrieve codes not just misfiring ones, check fuel system status, select live perimeters; fuel trims, ECT, Calculated load, MAF, cylinder misfiring counter, injector on time, engine rpm.. These basic datas will give you an idea of what the source of the misfiring is; fuel, air, ignition or mechanical. Depending on when the misfiring normally occurs, is it on idle or while driving.

A REAL WORLD CASE HIGHLIGHTING BOTH ACT
A 2005 Toyota 4runner with 3.5L engine size was brought to my shop with several issues including misfiring. Since the fuel system status is open, I usually find it difficult working on such vehicle. I hand it over to my mechanic.

The ART
He unplugged several of the coil connectors and gave me his results; two coils will be replaced, all plugs will be changed and the injectors will be serviced. I obliged and he did all of that but no result. Total cost #50,000.

I took to a second mechanic friend with a scanner, expecting him to first plug in the scanner and see what codes are logged in but just choose to go the same way as the first. We replaced an injector against his three and replaced all spark plugs, same thing no result.

The SCIENCE
The owner was getting frustrated so do I.I took the vehicle home, plugged in my scanner and see what data I could retrieve and analyse. The misfiring codes were P0300, P0304 and P0306. I picked some live data without the trim; engine rpm, calculated load, MAF, misfiring counter, ECT, injector pulse width. MAF was 3.8 g/s, rpm was 750, ECT was 75 degree Celsius, injector on time was 3 milliseconds, misfiring counter 4 & 6 were heavy and about 2 others were light, calculated load ok but no correction factor which is the trim. Analysing these datas without the fuel trim gave me the impression that the issue is on the fuel side. I pulled out my engine fuel analyzer to see fuel pressure, behold it was 35psi which is below Toyota standard fuel pressure on idle. With this instrument I checked the pump backflow valve, injector leakage and dynamic pump pressure, the pump pressure failed the test. The tank was dropped and the filter washed and pump pressure returns to normal. All misfiring codes were gone, vehicle runs fine.

The TAKEAWAY
While the ART is very helpful, modern technolgical advancement is pushing the art to the background making scientific approach the necessary option.

Do you think in the maintenance of modern vehicle, the scientific approach should be adopted more or the traditional ART. Please leave your comment.

I wish to make this a thread where issues of automobile electrical and electronics canbe discussed.

One of the main driving force of modern technology with regards to hard ware is Electronics. Smart Electronics seems to be a Topic only reserved for advance nations and is a dreaded Topic for many of as individual. Without Electronics all software development would amount to nothing.

Despite the complexity of modern electronics, it has become a focal point for modern life, in our homes we find them, in our businesses they are there, in the field of medicine it is also there, in defence we find it, and then in automobile it is driving innovation to a new level. I checked this forum but didn't see any discussion about it. Every car owners dread the thought of having electrical issues in his car, unknown to them it is electronics they are afraid of. Auto Electricians are always cought nipping, especially when face to face modern vehicles with complex electronics issue. Where the scanner stop, electronics starts.

In this thread, i will be demystifying the issues of electrical electronics in automobile; seperating electrical from electronics in automobile, how electronics has impacted heavily on the mechanics in modern vehicles, how mechatronics is becoming a new branch of engineering and its common application in modern vehicles, and how you can build a career in modern vehicles electronics.

Please just keep following us, and share your thoughts and view on this topic with us.

Fregene Harry
Technical Director
Advance auto electronics and diagnostic Ltd

Hello all, am glad to be part of this forum though have known this forum for a while but never thought would be a member someday. My joining this forum is as a result of my indept discussion with ai yesterday. I have been under severe pressure to move out of nigeria with my technical expertise, infact the pressure is even more from my wife and close friends. I have done substantial amount of investment in automobile electrical electronics and diagnostic here in nigeria, my primary goal was to help youths see the enormous opportunities available in the aforementioned areas, which is the bane of modern technology in Automobile. However, it seems the nigeria field is still far away from it and not even yet ready for the rapid change coming. With my indept discussion with ai yesterday, i found new opportunities both within and outside nigeria, one of which is my joining this popular forum to share ideas and also seek new ideas.
Automobile electrical/electronics have gone far complex than many think and it goes from one car brand to the other, some structures can be pretty less complex like the Toyota to complex ones like the Porsche, BMW, VW, jaguar, jeep etc. The year model also affects the complexity. Not making things easier is the introduction of electronics into virtually areas that were once purely mechanical, giving birth to mechatronics.

Now where are the challenges coming from, it is the inability to apply updated theoretical knowledge to solving real world problems. We have brought in several graduates of engineering for training but the story is not too different. They just want to rely mainly on the scanner to pinpoint the location of the fault, hence once the scanner mentions a component by virtue of the code, the component is replaced if it didn't work, the control unit will go. You could do either of them or both the problem solved. You could also do both and the fault persist. That is the reason why the guys who specializes on a particular make has more advantage, because they easily take part from one to test the other to verify a faulty one. Additionally, scanners are not substitute for electrical/electronics skill, scanners are more like your smartphone, how much you are able to use it depends on how much knowledge you have about the phone's application, so is the scanner.

In fairness to the truth, many of our Automobile Technicians are trying, because when you look at the knowledge base available, you will wonder how some of them are able to navigate through the complex systems in some of these high-end vehicles. But many of them end up heavily compromising the electrical/electronics circuits in the vehicle. Almost all vehicles brought to us, once parts have been replaced and nothing happens, the circuits will be the next victim. Even the car owners are not helping issues, when you advise on certain repairs especially in the field of electrical/electronics, they just want to look for someone who would do as they pleases. There are times when customers will appeal to me, for them to bringing experts from Lagos on the particular make, I do allow them. Whenever these experts arrive, I usually observe them, they just coming and start working without asking questions. That is a first sign of failure, it just like a Doctor who starts prescription without making enquiry from a patient. Even if you know the brand like the palm of your hand, you still need to ask questions either from the car owner or from the Technician working on it. The reason for that is, that little data may just help send you through the right path. Whenever a technician enters my shop I judge him by his asking questions, the instruments he is bringing along and the resource material he is also carrying.

A case in point is a 2000 s80 2.4l that was brought to my shop, I have initially told the customers I don't work on converted vehicles especially in the areas of electrical/electronics, they are like sick man who drop dead suddenly. The owner of the vehicle is based in U.K, he brought two right-hand driving vehicles, one Benz and one Volvo, they were both converted in Lagos few years ago. As I write both cars are no longer roadworthy, in fact he just sold the Benz for #1m and the Volvo abandoned in my shop. When they brought the Volvo to my shop behind me, I was not happy because i told him earlier I don't work on converted vehicles. But then that is how I got to work on different Vehicle make and help t to understand their technology. Besides, this will mark the first time am working on Volvo. The first thing I usually do is to research the country origin of the vehicle. This Volvo is from Sweden not the U.S. brand, then I knew it is going to be a tough nut to crack because most Volvo in Nigeria are from U.S and the S80 model are all either 2.9l or T9 which may not be compatible with the Sweden model 2.4l in terms of part. I only assured the man that as for the circuitry, he should have no fear, I will fix it. I really did as promised and the entire circuit lines: electrical, electronics/network were rectified and communication was restored and so do the dashboard light. However there comes an issue with the CEM, which holds the entire immobilizer data and also serves as the central gate way between the two CANBUS used in the vehicle. I really learn a lot, the CANBUS structure was very different from all other CAN systems have worked on. The CANBUS protocol is the most popular BUS being used in modern vehicles. The rest usually have a 60ohms terminating resistor on the slaves and 120ohms on the Master(s). So if one slave is faulty, it does not affect communication to any other control unit, only a failed or dead master can affect communication to other control units, but if that network only has one master, then the entire network goes down. That is why sometimes you may find it difficult to communicate with control units in CAN C but able to communicate with the interior CAN B if this is the protocol use in the interior communication. But as for this volvo it is looped in and out with the two CANBUS used Fast CAN and Slow CAN. So if a control unit goes down all other control units looped from it will also go down from the network. So let me go back to the CEM, checking my programming tools i found non of them could read that chip type. My advice to the man is to source the ECM, TCM, ECM,and Key from a disused s80 2000 from U.K where he bases. But people advised him that those parts could be found in Lagos, he brought about four sets of those parts, they never worked. He decided to bring a 5th set with two volvo specialists from lagos which story i was sharing initially. Observing these guys as they work quickly give me the impression that nothing will work, because no scanner, no multimeter and no resource information so how do they want to go round it. After working for about two days, they went back to lagos and advise the owner to buy a complete wire harness for the dashboard, the cost initially was #250,000 and later they raised it to #400,000. What i noticed in their working style is the use of knife and testing lamp, they will Peel out portion of the wire insulation and test with the lamp, that was what they were doing with the whole system. The man was angry and later appeal to me if there is anything else I can still do, but I told him there is nothing I can do other than what i advised earlier. His concern was, I said parts but these guys are talking of harness inclusively. Already I knew they must have blew up the system, I plugged in the scanner to see what went wrong, only to find out that control units I was able to communicate with am no longer able to do so. The CEM, ECM and TCM were incommunicable. The dashboard light no longer works. At this point, it is all about your troubleshooting skill to fish out what went wrong. Once you couldn't communicate with control units, the first step as a technician is to check for power and grounds with the aid of a diagram and ensure they are sound. There was no power to the TCM which is looped to the ECM. The power to the TCM comes from the CEM, when they peeled off the insulation of some of these wires in the CEM, they didn't insulate them back and in the process of working, these wires short together and blew up both the TCM and CEM. Unfortunately, they couldn't know where the problem came from hence they feel the harness should go. We later resolve it with separate set of TCM, ECM, CEM and Key. The Engine started and raise well but couldn't idle due to the throttle body valve being part of the network. The valve is not compatible with the ECM. I Can go on and on with several experiences even with established shops.

Let me address the issue of converted vehicles mostly in areas of electrical/electronics. If we can take into consideration the basic principles of electricity, it will help us as we deal with electronics circuits. Initially when done, the vehicle might work fine but some systems will have to be compromised without even the owners knowing, the reason been that most Nigerians are simply concerned with drivability issues. During this conversion process most wires will be cut and join together, these extra joints are mostly weak and far below standard. Electricity is the flow of electrons, electrons flowing through a wire, will have to overcome certain resistant present in the conductor. The work done to overcome this resistance will appear in form of heat, thereby raising the temperature of the wires. Now if you create these weak joints, an initial foreign resistance has been introduced into the circuit which will cause electrons to do more work at such points. The heat generated as such points would create an expansion when hot, when the conductor cools down it can't contract back to the original position from which it expanded and thus introducing new resistant. For every rise in resistant a corresponding temperature rise occurs. In time, the weak insulation tape will give way and shorts will start, loose joints causing voltage drops and this drops start affecting power to control units and components. In the long run the maintenance cost for such vehicles will go up. If the same thing is done to communication lines as in this volvo,that is even worst because communication lines are very sensitive to voltage fluctuation and interference. This whole process of conversion violates the principles of electricity namely ohms law, KVL and KCL. Electricity do not have theory and practical, it is either you adhere to the principles or you violates them.

The bulk of innovation in modern cars is based on electronics and even the current trend down to the future is still based on electronics. Therefore there is no way we can come onboard without following these well difined principles and ensure they formed the bases for all our applications. With these challenges comes opportunities for science and engineering students to take advantage of what technology has presented in the field of Automobile. The current skill set can not make up for it neither the ones coming out from the vocational schools. I have seen students doing their IT in most workshops and you ask what sort of hands on practical these students will learn, it is what the shop has that will be giving to the students and all those non applicable theory will just go into the dustbin once they start practicing. The scanner has been a source of tremendous help but can't still take the place of Electrical/electronics, human critical thinking, data analysis, hence there are so many other instruments both mechanical and electronics. A guy come to my shop in warri and wanted to work with me as a mechanic. I interviewed him, he is a graduate of mechanical engineering, he did his NYSC with a major dealership in Lagos and also worked with them for two years. Then comes his work experience, he said they usually install and uninstall and other mechanical works. I brought an Engine system analyser, I asked him if he had experience using it, he told me point blank that he has never seen that instrument, so i said to him you need to start over with instrumentation and measurements. There was even one in Benin city run by the Lebanese, they called me for a GX470 having a hight activation. Getting the story is not different, the entire circuits were so distorted that you hardly think it is coming from that vehicle. I never wanted the vehicle in my shop, so i told them we are going to fix the issue right in their own shop. I was assigned s Lebanese and two nigerians. The beauty of electrical/electronics skill is that you don't bother about what were damage, instead you keep your focus on your road map. First, i printed the entire diagram for about three network since the hight activation control unit is in a different network but needs to work with control units from other network. The second phase was to begin communication with all the control unitd from across the different protocol and mark out those that failed to communicate. The third phase is to study the network thoroughly with those units that failed to communicate. The goal is to see if the network is ok, if all control units in a section of the network failed tocommunicate then something is wrong with that section, but if some communicate and some do not depending on how they are placed in that section, we could tell those units have issues.
The fourth phase is to work on the control units that failed communication by checking all their power and ground with a wiring diagram, those that had faulty power were resolved and communication was restored. We did same thing with the gateway but yet no communication. The moment we replaced the gateway, communication to the hight activation was restored and the system start functioning properly. The point is this, if you don't understand how the system function and knowing the units that play part in the hight activation, it may be very difficult to fix especially for vehicles like the gx470 whose systems have been badly damaged.

I really there is a huge opportunity in the automobile industry which is still very untapped. I believe it could open ways to othet aspect of modern technology as the applications can be found in other areas of midern technology like aerospace, defence, marine, medical, drones production e.t.c
The skills in automobile electrical/electronics are very transferably. I came from the industrial sector infact my speciality is electrical/electronics engineering and today i can decide to transit into other areas with easy, it is one of my options currently. But if you ask most of the other guys, that is not the case, they could either transit to part sales or vehicle sales or quit all together.
I also believe we should help with our talent and not just to die with it, in this regard i am setting up a training for engineering and science students and even auto electricians who want an upgrade in Automobile electrical/electronics. Is a project am working on since for a period now i lost interest in working full time. I merely handles some customers vehicles on the bases of getting other workmen such as mechanics, panelbeater, spray painter, locksmith. Of all the workmen i do use, the mechanics are the most difficult to deal with. They don't like following instructions, they always assume they've been on the job for ages. I handled various high-end vehicles and in most cases i do the overall diagnosis and instruct them on what i want them to do, to my surprise these guys will end up breaking parts, bolts left out and yet no remorse when i found out. These high-end cars like Bmw, Porsche have a different mechanical built compare to the common brand. The last job i did almost got me into trouble, it was that job that made me decided to focuse primarily on electrical/electronics. It is a common brand, 2005 toyota 4runner. The mechanic replaced the top gasket because the engine did overheat, in the end the mechanic just time the engine with one CAM off and the other camshaft actuator broken and plugged with a bolt. The vehicle uses a VVT technology and i told him he needs to retime the engine again without knowing what he did to the camshaft actuator. He even Bragg to me that he has been timming toyota engine for the past 20years in lagos before coming to Benin, he was even revving the engine very high to prove the engine is ok. He said if the timing is wrong the engine won't start. I just laughed, i pointed to him this engine is using VVT-I technology, for the base time you have two intake cam timing, if one is off alittle and the other is right, the computer will use the correct one to calculate ignition timing. It is different from a four cylinder engine with just one intake cam, once not properly synchronized the valves will be opening and closing at the wrong time which will cause low engine pressure. The computer calculate the ignition timing base on imputs from engine sensors and others. Atlast, he agreed to open the engine timing chain cover and i asked him to turn the crankshaft 720degree clockwise, he did and we found out the bank 1 cam was off by 2inch. I also saw the actuator he broke from bank 2. Assuming this work was done for others, that engine won't last long before mechanical damage set in. I actually did not want to dive into the mechanical, it is a different kettle of fish. My point is this, there is no way we can develop our technical skill without a strong theory base. It on this ground i am setting up the training program. It was not always easy and right while i was developing myself on this, i had some failures like someone solving different mathematics problem using a standard formula. But i always go back and find out what data i miss even if someone else solve the problem i will still follow through to make sure i get the missing data. But now the rewards are trickling in and that is the same principles i want my students to adopt.

On a final note, i believe there are brilliant people on this forum who will share their thoughts with me on this. We really need to beaf up our skill set and close the gap.

Thanks
Fregene Harry
Technical Director
Advance auto electronics and Diagnostic Ltd