10.02.2019

Brought on a tow truck: "Does not start."
I ask and clarify: "For no reason, for no apparent reason, it stopped starting, or was some work done?"
Exactly. It turned out that before that, some kind of body work the car was in an accident. No more information, except for the only one: "Tried to start - does not start." Further sad: "Many have tried."
Well, enough for the initial push.

Since the car is profile, then you need to look at it with the "correct" MUT3 scanner. What I wanted to find out: to see the communication of control units with each other.

And it turned out that there was a problem with the engine control unit: not a single unit could communicate with it.

Now there is enough information to move on to "heavy artillery", to an oscilloscope, you need to clearly see what is happening, and for what reasons there is no connection. I connect, I look: at ignition on no polling via CAN, no answer, no code packets, silence. And this explains everything: in this state of affairs, the engine will not start, he does not even know that they are trying to start him.

And on the one hand, this pleases: there is something to think about and where to stretch your brain: "An intermediate negative result only pushes forward!".
And now a few words about the benefits of the Motordata program: if you need to find a scheme very quickly and think, then this is done in a couple of mouse clicks:

Why do you think this diagram was shown? Yes, I also highlighted in red and bold the right one for my story?

Yes, because there is a certain charm to profiling for certain brands of cars: many years of studying them allows you to create a certain “library of typical malfunctions” in your head.

Is this also a problem here?
No, it’s not “too”, but “similar”, but this is a certain kick to turn thoughts in the right direction.

What I mean: before the control unit, the Kan-bus signal passes "draft" through the control unit ABS system. Without knowing this feature, you can search indefinitely for a similar or other malfunction.

That's what for quickly(I emphasize!) I opened the circuit in Motordata, looked and made sure that the memory does not fail. What happens here: if you remove the connector from the ABS, or if the ABS unit is faulty, then there is a high probability that the car will not start. Such is the original specificity on such Galants.

I'm checking. I'm calling. I am convinced that the wiring itself is intact, and the malfunction may be hiding directly in the ABS unit.

But since the initial task is to start the engine, I start to “collectively farm” a little, but this is not scary at this stage, because the main thing here is to check my assumption. To do this, I make temporary jumpers on the connector:

And everything started to work out. Code packages began to reach the control unit via Kan-bus:

The next step is to specify the malfunction: WHAT specifically failed?

I carry out checks and make sure that the malfunction lies in the ABS block itself, most likely, during the accident, some kind of “internal break” occurred, as a result of which the signals stopped passing through the block in transit and caused the “engine does not start” malfunction.

And now step by step, testing and critical: "What did you do right and what could not have been done."

A conversation with a client.
The condition is mandatory, because if you build a conversation correctly, you can find out and identify such "little things" that will lead to a solution to the problem.

Scanner check.
A prerequisite: the machine is profile, the scanner must contact and show the existing errors. If you suddenly didn’t show it, this is also good, as it gives an impetus in the right direction.

Motordata, scheme.
Required condition. To do this, one must be able to "read" the diagrams and understand all the notations that the diagram provides. The key word here is "scheme", not necessarily the Motordata program, it's just more convenient for me to work in it, since it is fast and understandable.

Comparison, analysis, comparison.
At this point in the diagnosis, you need to turn on your head and pull out "typical malfunctions" from it. It's easy enough if you have some experience. If there is no such experience, then here is a tangle of "typical malfunctions" to help you:
Enter what you want in the search bar and look, for example:
“Every car and every manufacturer has cars that have so-called “typical faults”. That is, these are faults that are repeated on every second car (give or take).”
"Typical malfunctions of car units are considered, the main ways to eliminate them are given."
"Typical malfunctions hybrid Estima in the 10th body has long been no secret to all owners. It breaks and fails PRACTICALLY EVERYTHING. Starting VVB and ending with an inverter, i.e. there is not a single reliable knot from "tip of nose to tail"
And so on, in short: "Search to help you." Or here

Your technical equipment must be impeccable - because the time you have is the same money that we hope you also have. Don't lose either one. If a missing tie or a pant leg burnt with an iron can cause a disruption in a business meeting, then what can we say about a car that does not want to start an hour before the scheduled negotiations.

Early in the morning, freshly shaved and full of great plans (the child is going to school, the wife is going to the hairdresser, and he is forging a penny), you jump into the car, "key to start" and... What the hell... One more time. More ... Nervous manipulations with the key and pedals do not bring success. The day is ruined from the start. Plans and mood - down the drain.

Take it easy. No need to rush under the hood in an English suit and, smearing oily dirt with a tie, try to make a diagnosis. In 5 minutes, most likely, you will not cure. Take another car, and leave the treatment of a sick friend until the evening. And it is better to entrust it to doctors with a good reputation, especially if you have an expensive car, and you are not a specialist. That will be cheaper. Well, if your friend is well known to you and you consider yourself a healer - well, try it yourself, if you are not too lazy to get dirty or there is no other way out.

The diagnosis should be made calmly

Study mentally the symptoms. First, is the starter spinning? And if so, how cheerfully? You already know the answer - remember what happened when you first tried to start the car. If you don't remember, try again.

If the starter does not turn at all and does not even click the traction relay when the ignition is turned on, then it is either faulty (you can close the hood and follow the advice above: "Take another car ..."), or the trouble is with the battery - turned off or sat down. Only in rare models can the starter power circuit be protected by a fuse - a 300 amp commercial - it is easy to find, especially if you know in advance where it is located. If the battery is to blame, then, as a rule, all electrical equipment does not work either. The simplest and easiest case is that one of the terminals has fallen off or dirty, but the battery is in order. Tighten the terminals on it and on the starter (if any). If it turns out that the battery is completely dead (forgot to turn off the headlights for the night), you can still leave. But with outside help. Here, as they say, options are possible. You can try starting from a push, from a hill or from a tow. Do not try to get around the pitfalls: a car with an automatic transmission or electronic injection fuel (if there is an electric fuel pump) cannot be started by these methods. You'll have to smoke at a neighbor's. True, for some machines this can lead to damage to the computer (read the instructions for the machine). If the starter is spinning, but sluggishly (this happens in summer, in winter this is a subject of a separate discussion), most likely, the battery is almost completely discharged. This will be visible from weak light headlights or frail signal. In this case, the above options for outside assistance come into play.

If the starter turns briskly, and the engine does not respond to attempts to start it, feel free to exclude everything related to the battery from further consideration. Blame the ignition or fuel supply system, you can't go wrong. When diagnosing and treating each of them, a systematic approach is required. It is better to start with the ignition - there are problems more often. Especially in wet weather.

From a spark will ignite ...

So, you need to look for a spark. Your car may be equipped with a classic (simple) contact ignition system, a rather complex electronic non-contact ignition system, or some combination. In any case, the system consists of three parts. Part one is low-voltage (breaker contacts in a classical system or a special sensor in an electronic one, plus a box with electronic filling that forms a spark). Part two is a step-up transformer, referred to in the world as an ignition coil. Part three - high-voltage (mechanical or electronic distributor and wires through which the current high voltage leads to candles). And, of course, the candles themselves. Checking all this economy should be carried out in stages and it is better to start from the end.

Stage one. High voltage part of the system. Check if there is a spark on the center wire - this is the one that connects the coil to the distributor. The tip of the wire must be removed from the distributor cap, brought closer to any part that has good contact with the mass of the car (it doesn’t matter if it is painted or not), and fixed so that there is a gap of 5–7 mm between the tip and the selected part.

If the ignition of your car is electronic, you need to fasten the wire especially securely - if it falls to the ground, the electronics will instantly order a long life. For the same reason, you can not strike a wire on the body. We also do not recommend holding it with your hand, not even your own - it will shock you great.

Stage two. Turn the engine over with the starter. At the same time, look at what happens at the tip of the wire. There are two options. More favorable - there is a spark. Powerful, accompanied by a loud click. This significantly narrows the field for further searches.

The first step is to remove the distributor cap. Under it can be damp and dirty. Through such a "conductor" the spark readily jumps anywhere, but not where it is needed. Wipe, scrub and dry. At the same time, it is harmless to clean the contacts of the distributor, for example, with a fine sandpaper. Examine the so-called "runner". If you find a dark trace of electrical breakdown on it or on the distributor cover, the part will have to be changed.

In the most biased way, check the wires coming from the distributor to the candles. Wires and their lugs must be dry and clean. If, in your opinion, everything is in order with them, you can put the cover back on, reconnect and try to start the engine. If the malfunction was hidden under the cover, the engine will start or, in the worst case, at least start to sneeze. The symptom is also favorable - you are on the right track. True, you will have to turn out, clean and dry the candles - in an attempt to start the engine, you filled them with gasoline. If the engine does not even sneeze, the candles will still have to be turned out, cleaned and checked. It's easier if you have a spare set.

If you have already got to the stage of turning out the candles, you can quite effectively (and effectively) check the entire ignition system as a whole. By connecting to the inverted candles high voltage wires, collect the candles in a bundle, like carrots, and wrap them directly along their threaded part with bare soft wire. Make sure the wire makes contact with each spark plug but does not touch the center electrodes. Connect the free end of the wire to ground. Having placed a bunch of candles in a place convenient for observation from the passenger compartment, turn the engine with a starter. At the same time, cheerful sparks should jump between the electrodes of the candles in turn (in accordance with the order of operation of the cylinders). If so, then the entire ignition system is in order. The sound of the engine at the same time will be very unusual - do not be alarmed, because it is spinning with the candles turned out. Don't spin for too long. Worse, if at the second stage of the test there is another option: there is no spark between the central wire and the "case". So, it's not about high voltage circuits. Further searches will be more difficult, evaluate your time and desire. If both are available, proceed to the third stage. Check if voltage is applied to the ignition coil. This is easy to do with a tester, and if it is not there, you can use the engine compartment light. True, you need a couple of wires to connect it to the coil. In a classic ignition system, you need to connect a light bulb between ground and the input of the primary winding.

At the third stage, as usual, two options are also possible: voltage is either applied to the coil or not. If it is supplied, the coil is to blame - breakdown or short circuit, which, however, happens extremely rarely. The coil will need to be changed. More often there is a bad contact in fastening the wires to the coil. Or the same wet dirt, through which the spark flows away, no one knows where. Sometimes the coil is polished to a shine, but an invisible very narrow strip of dirt remains under it - a good conductor.

If, at the third stage, you made sure that no voltage was supplied to the coil, the electronics or contacts and unreliable connections in the low-voltage part of the ignition system are to blame. You can’t cope with electronics (switch and, less often, a sensor in the distributor housing) - special equipment is needed to diagnose them. You can only pull the sensor connector on the distributor housing - suddenly it will help. If you have a car with a classic contact ignition system, you can look further.

Remove the cover from the distributor and inspect the breaker contacts - they can oxidize, especially if the machine has been standing still for some time. Contacts must be carefully cleaned with a thin sandpaper or a special file.

Pull the cleaned contacts so that they either close or open. The voltage on them is only 12 volts, so you can pull it fearlessly. If the cleaning did not help and the voltage to the coil is still not applied, once again we advise you to stop trying to resuscitate the car for a while, since difficulties will begin further.

If voltage has appeared (when the contacts are pulled, the light flashes), restore everything that has been unscrewed and disassembled, start the car and, perhaps, still have time to go about its business. If it doesn’t start, but at least sneezes, turn out the candles and ... (see above).

Do not press to the floor - it will not help

It may also turn out that the entire ignition system was checked, everything is in order in it, and the engine, even if you crack, still does not start. So, problems with another of the previously mentioned systems - power system, t. e. supplying fuel to the engine.

If you have an injection machine ( injection system supply) of fuel - do not touch it (to the system). You can only come to the conclusion that it was she who broke down: there is a spark, the fuel is suitable - it means that she, darling. Treatment only in a hospital. At home and with handicraftsmen, repairing it is useless and even harmful.

In normal carbureted engine fuel system simpler - a tank, a gasoline pump, a set of pipelines and a carburetor. Here you can poke around yourself. The first step is to make sure that gasoline enters the carburetor. Disconnect the hose from the carburetor and press the manual priming lever. If a fairly powerful stream of gasoline has scored, everything is fine, it's time to move on to the carburetor. It happens that gasoline is supplied to the carburetor properly, but for some reason it does not enter it. If you have time and desire, take air filter, then ask someone to depress the accelerator pedal sharply. Or you can sharply pull the drive cable yourself throttle valve. At the same time, look into the carburetor from above (the air damper is open, otherwise you won’t see anything): if a trickle of gasoline does not appear in the first diffuser, it means that it is not in the float chamber. It is not there because the valve needle is stuck or (it happens not very often) the fuel filter in the carburetor is completely clogged - it is located in front of float chamber. Or clogged jets. The filter is cleaned by blowing, but if you don’t have the necessary skills, it’s better not to mess with the carburetor internals at all, deal with sticking of the needle valve, clogged jets and other subtleties - let the experts do it.

If there is a trickle in the diffuser, pay attention to the carburetor starting device - it often fails. On foreign cars, starting from about the 70s, it is used automatic control air damper. The device, without your participation, depending on the temperature of the engine, closes or opens the damper as much as necessary, enriching the mixture when the engine is started. If this automation works, you can try manual manipulations with the air damper, but there are a lot of options and there are no universal tips. Before starting manipulations, connect and secure the previously disconnected fuel hose. The air filter can not be installed yet. If it starts, let the engine warm up and with God (after returning the air filter to its place) .. If, when checking the fuel supply with the fuel pump, it turns out that gasoline is not coming out of the hose or the stream is very thin, the cause must be sought in clogged pipelines, a fine fuel filter or the gas tank itself - you can well demonstrate your skill by pumping the gas line with a tire pump in the opposite direction to the movement of gasoline, i.e. e. from the carburetor to the tank. In the tank, booming, gurgling sounds should be heard.

With filter fine cleaning fuel is simple. Although on almost all modern models it is made in a transparent case, the degree of contamination cannot be visually determined. Dirty filter will allow you to start the engine, but will not allow you to drive normally. If it is completely clogged, the engine will not start. The most effective check: remove the filter and, if there is no new one, temporarily replace it with a suitable tube, for example, ballpoint pen cases, preferably transparent - you can see how gasoline flows. Do not try to clean the filter - a sealed (or sealed) case cannot be disassembled.

If you have come to the conclusion that your machine does not work fuel pump, and there is no spare at hand - "Take another car ...".

We saved the rare but most unpleasant diagnosis for last. If the starter is working properly, you have already spent a lot of time and made sure that the ignition and power are in perfect order, but the car, nevertheless, does not start - it is worth inspecting the camshaft drive belt. However, decide for yourself, this check can be carried out at the beginning, especially if the engine has already passed more than 60 thousand. The difficulty is that you have to remove or at least partially bend the upper part of the plastic casing covering the belt. Perhaps the teeth of the belt were cut off - in belts, like in humans, teeth are lost from old age. In this case, the camshaft does not rotate and the engine will not work. It is clear that a toothless belt needs to be replaced (those who have a car with a camshaft chain drive do not face this trouble). The procedure for replacing the belt is not difficult, but troublesome. It is carried out in a hospital. Well, if everything is limited to replacing only the belt, and not bent valves or the entire head of the block - this also happens.

Fewer freeloaders

It is worth saying a few words about the battery. Since it is maintenance-free on most modern cars, it makes no sense to give operating instructions here. We will give just a few additional tips on how to keep the battery viable longer. Do not get carried away stuffing your car with additional energy consumers. The fact that the energy balance of the car has a certain margin that allows you to connect two or three "freeloaders" does not mean that you can hang six horns and ten fog lights on the car - have a sense of proportion. In addition, if you connect unforeseen tsatski yourself, there is a high probability of damage to the insulation. And in general, as practice shows, any, even the most qualified, surgical intervention in the electrical wiring of a car sooner or later makes itself felt. Trouble.

If your battery is dying, try not to chug your engine during countless city stops. Nothing rapes the battery like frequent use of the starter.

And the last (this applies not only to the battery, but to all electrical equipment in general). Remember: all terminals, contacts, wire lugs must be dry and clean and fit well to the "destinations". Dirty, oily insulation breaks through sooner or later, and burning and oxidation of any contact surface can serve as the only (and sufficient) reason for the failure of the ignition system. Or fire.

You can stop there. Meticulous motorists, of course, drew attention to some superficiality of our advice. We admit that we deliberately do not want to delve into the wilds. In order not to provoke you to self-treatment - it does not lead to good. Understanding the nature of pain in the lower abdomen on the right does not mean that you yourself have to remove your appendix. But you must accurately describe the symptoms of appendicitis to the doctor. It helps a lot with the treatment.

From the first words - "bull by the horns." Don't mind what we're talking about Mitsubishi models, and on the screen Prius. This is for an example. We look:
Here, clearly, with drawings, it is shown what work should be carried out on a Prius ZW30 model of 2011-2012 release. Next to the description (not shown), it says after what time to carry out this or that maintenance.
Everything is clear and understandable. And, if maintenance is carried out as the Manufacturer advises, then the owner of the car will have much less problems - unlike the option: "Let him drive until he breaks down." And in every right car service must be similar TO cards.

Let's go back to our Mitsubishi . It was Galant, "American". 2.4 liter engine, problem: "Does not start."

The following was done by the client: “hard reset” of the control unit - indeed, the Internet is simply indispensable for conducting experiments on your car! From there you can subtract a lot ... and then throw yourself with a saber at your car - without thinking about the consequences at all. It's good that a "hard reset" does not carry anything terrible: remove-put the battery terminal. But there are other tips on the Internet. And they do not always have a positive effect on the health of the car.
So, the "hard reset" did not help to start the car, and then the client made a wise decision: "To the rope and to the car service."

Well, we also decided “not to philosophize slyly” and for a start we checked the basic and simple: a spark, impulses to the injectors. There is nothing. Nothing happened when cranking the starter.

What's next: to emulate signals, there is a self-made device, simple, reliable, - in the photo then 01
By the way, I recommend making this - if someone else does not already have something like this. If you need a diagram, write, send.

We check- photo 03. Great signals. Everything is. Thus, we cut off the problems with the engine control unit that the client pointed out and made sure that the issue rests on the control unit and its circuit, and on the sensor crankshaft.
On the photo 04 and 05 shows the root cause of the problem.

What is in the photo: the very thing that few people pay attention to when carrying out the next maintenance or when replacing the timing belt (gas distribution mechanism).

This problem is not uncommon, on technical forums they write about it all the time:

"Balance Belt"
“... He was pulled under the timing, which jumped. As a result, the axis was cut in half, the bolts securing the axis to the camshaft covers were torn out, and one cover burst. At the moment I am looking for ways out of this deplorable situation.
“And the balancer belt cost me 80 kilo-rubles to overhaul the engine” (author's spelling)

Well, what do we see? "There is a problem." And it's not just on our car, it's regular, judging by the forums that popped up randomly in Google searches. What could be the reasons for this? In my opinion these are:

Life position: "let him ride until he breaks"

But our client was lucky. The truth is relative, but “lucky” - everything ended only with a replacement, nothing was broken, nothing was broken. And it could! A very recent example audi car, see photo:

You can clearly see what broke off the valve (in the photo then 07 only one valve is shown ... and don’t look that it lies on a box from Toyota, there was simply no other stand), and in photo 08 a cylinder with scuffs and a broken piston, the block head is also not subject to restoration. There was only one way out: replacing the motor. So our client, as they say, is "wildly lucky."

Some of the causes of such a malfunction have already been mentioned above. I will add:
If you change the belt - buy it from a trusted supplier. Make sure a hundred times that it is not "left" and will last a long time.

And the belt that we took off ( photo 04 and 05), it was of incomprehensible origin or served this motor for too long: the belt was in such a condition that it was worth picking up the teeth a little with a fingernail, as they crumbled. Before replacing the belts, the client was simply and calmly explained the difference between a "brand" and a "simple" belt. The second one was much cheaper. And the client made the right choice:

- I'm branded, please put

Not a question, ordered, brought, delivered.

And finally, read the reasons again:

Late maintenance
Poor quality maintenance (improper belt installation, etc.)
The use of low-quality components (fake belts)
Life position: "let him ride until he breaks"
- and decide for yourself how to do it.

Kudryavtsev M.E.
© Legion-Avtodata

In the last article of our "Workshop" section, the reader, as a small problem Volkswagen Passat could not find experts official dealer. Today, the owner of an old Mitsubishi Galant, Dmitry, will share with us his experience of finding a small malfunction that prevented the car from starting. As in the previous story, specialists from the stations Maintenance couldn't find her.

My 1992 Mitsubishi Galant has a lot to do with it. interesting stories. I bought it on an ad, like any average Belarusian. The car is not young, I understood this very well, but for its age it is quite good: full power accessories, electric sunroof, headlight washer, heated mirrors, etc., even lends itself computer diagnostics. But after a couple of months, the engine starts to “eat oil”. The people looked at me with big eyes, when every time I bought 20 liters of gasoline and a liter of oil at the same gas station, filled it all up and drove on.

A little travel, decided to make a major overhaul of the engine. This is where my black streak began. After overhaul at first the engine did not want to start, but then the reason was quickly found: the high-voltage wires were connected incorrectly. Having set something up, I went home happy, but my happiness did not last long: the next day, the red warning light on which the battery was drawn came on, which meant the loss of its charge. After measurements, it was assumed that the "chocolate" in the generator burned out. We bought, dismantled the generator, soldered the “chocolate” - the warning lamp does not go out. It was decided to take the generator to the specialists. It was shocking that I had to change almost the entire generator. We replaced the diode bridge, winding, rings, we also changed this “chocolate” - in general, now I was holding a new generator in my hands. But all this, one might say, is a prehistory.

Of course, now the battery charging warning light went out, and I again went home happy. But the next day was preparing new surprises for me, the car stopped starting. They towed the car and started to figure out what the problem was. First of all, I was alerted by the fact that when the key is turned, the “check” does not light up, which should burn for 6-8 seconds. This indicated that you have to buy new block engine management (which costs a lot of money!). Further, it was determined that the nozzles do not spray, there is no spark. The starter just spins but the car doesn't catch. But I don't have an immobilizer!

It was decided to look for a service station or a specialist who could solve this problem. Most of them immediately refused my car, others said: come and try to see, diagnose. I am from the Minsk region, it is unprofitable for me to tow a car from one service station to another, and no one gave me a 100% guarantee for repairing the car. The car stopped. I myself started looking for articles on forums with similar problems, and, as I said, all the articles rested on the electronic unit engine control.

After some thought, I suggested that there might be a problem with the petrol pump. At the very last moment, I remembered the gasoline pump relay, because it's easier to check. The fact is that if you need to get to the gasoline pump, you need to remove the tank, since in this Mitsubishi model there is no hatch through which you can get it. Having found the relay, cleaned its contacts, connected it again - the “check” caught fire, the car started up! I did not receive this information from any auto mechanic and did not find it on any forum! Now I am in search of a new "relay", but the car does not let me down. Here is such a seemingly simple, but unusual breakdown touched my car!