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What can happen to your multimedia computer (ССС, CIC, NBT, CHAMP, M-MASK) if it falls into the wrong hands?

What can happen to your multimedia computer (ССС, CIC, NBT, CHAMP, M-MASK) if it falls into the wrong hands?

Repair of multimedia devices requires high professionalism and knowledge of electronics, as well as the presense of professional special equipment, test benches and the ability to use all of these. But there are quite a few people with ambitions that go off scale so much that they begin to believe they can do absolutely everything. And they convince potential customers that they can do this. Usually, such incompetent repairmen give extremely short warranty periods for their repairs. You can see what the repairs of such “professionals” lead to in the photo below.

This is just a small part of the photos of those CCCs that personally fell into our hands after someone else’s repairs. We do not know what was going on in the minds of these “professionals” at the moment when they tried to repair these CCCs, but these people are clearly not doing their job. Despite the horror that we had to see after the «autopsy», we still repaired these CCCs, but it took us much more time than we expected. Да, мы ремонтируем даже такие сложные CCC по той же цене. Unfortunately, you will have to wait a lot longer than repairing a multimedia device that no one has tried to fix. It is not uncommon for a device to become completely unrepairable after such repairs, and in this case it must only be replaced. So before you carry your device to some unreliable master whose reputation you don’t know anything about, which has a low warranty period, you better to think 10 times, if you don’t want to carry the device 10 more times under warranty for rework. Because after such repairs, usually after a month, your device starts to malfunction. In the end, what does all this lead to? Every time a person hopes that by some miracle, he will be able to repair your multimedia device. Then pray that it does not break before the warranty expires; therefore it gives the shortest possible warranty periods. However, a miracle often does not happen, and after numerous attempts to repair your device, they lead it to complete non-repairability, depriving not only themselves of earnings, but also professional repairmen who could perform high-quality repairs and give a good warranty. And the client has to look for a used device, the warranty for which will be on average about 2 weeks. Moreover, that’s not counting the fact that the device needs to be properly updated and encoded. As a result, everyone loses except sellers of used parts. Although, it is not rare that they bring us purchased used devices that were out of order literally after 2 weeks of operation, but it is impossible to return or change them, since the guarantee for used is extremely small. And smart people, instead of looking for used ones again, bring us these devices for repair, receiving a 15-month warranty!

The main signs of substandard and unprofessional repairs that we constantly have to eliminate.

  • Overheating of electronic components.

Perhaps this is the most unpleasant situation, which most often leads to very complex malfunctions. Silicon crystals of microcircuits, transistors, diodes, etc. are extremely sensitive to overheating, as well as to the temperature profile of heating, which differs for different microcircuits according to the datasheet. If the temperature profile is not properly maintained, this either will lead to failure of the electronic component, or to accelerated aging and degradation of semiconductor crystals. Yes, perhaps, due to improper heating, the microcircuit will work for a while, but the question is how long: a year, a month, a week, or maybe a couple of days? This depends on how lucky you are. After overheating or ignoring the temperature profile, the microcircuit can also work at times, and at times go into hibernation, then after a while work again. In order to accurately observe the temperature profile, we use professional soldering stations, and the heating process itself is controlled with a thermal imager.

The temperature profile is the dependence of the temperature change on time during soldering. The standard profile consists of gradual heating to preheat temperature, holding temperature, heating to peak temperature above the melting point of the solder, short holding and cooling.

  • Low-quality flux usage.

The quality and reliability of soldering depends very much on the flux. Also, the flux must have almost zero electrical conductivity, otherwise there will be current leaks, which will lead to malfunctions of the electronic device. Another important quality of the flux is that it should not contain aggressive substances (acids, alkalis) that eventually destroy and oxidize the soldering point and surrounding elements. We often saw how after soldering with acid fluxes the pins of the microcircuits were strongly oxidized, and sometimes completely broke. Soldering microcircuits, especially BGA chips, requires very high quality fluxes. These fluxes are often counterfeited, so when buying on the market or ordering on ALIEXPRESS, there is a high probability of buying a fake one, even if the price is high. There are some cases when the same seller can sell you the original flux one day, and the next day sell you a fake one with exactly same label. Therefore, we order all professional fluxes only in the USA directly from dealers, which the manufacturer places on his website..

  • The presence of flux residues.

As you can see in the photo above, some “professionals” do not even think about flushing the flux residues. What does this lead to? Over time, dust begins to adhere to the remains of the flux, which will lead to leakage current due to its electrical conductivity, which leads to malfunctions and to a failure in the operation of the device. Also, some fluxes can accumulate moisture over time, which, in addition to current leaks, will lead to increased corrosion. We treat the flushing of the flux residues very carefully, since you can’t flush it using random products, otherwise the film that remains after the flushing solution can also become a source of leakage current due to its electrical conductivity. We only use high quality dedicated flux flushing solutions that do not leave any residue.

  • Poor soldering. Poor quality solder.

Very often, after other people’s repairs, we have to observe crookedly soldered microcircuits with the same unwashed flux. It is not uncommon for the pins of the microcircuit to be shortened together by almost invisible drops of solder, which are clearly visible in a microscope. In this case, we have to re-solder these crookedly soldered microcircuits and other parts, the way they should be soldered at the factory, along the way cleaning out the remains of the flux. The quality of the solder plays a significant role. Since contacts soldered with poor quality solder can eventually fall off from vibrations and temperature changes. We use only high-quality brands of solder proven over the years.

  • Identification of non-original items of questionable quality.

If we see that previous masters have replaced faulty components with parts of questionable quality (which may eventually cause a malfunction), we replace them with components which quality meets high standards. For example, on cheap Chinese counterfeit chips the marking may not be laser engraved, but paint, which can be washed off with a good solvent, and may not correspond to the original marking by numbers.

  • Missing or damaged parts.

Often, after previous attempts to repair a multimedia device from other masters, we have to notice the absence or damage of some parts. The most common damage (in addition to the absence of the parts themselves) can be broken leads, cracks, chips. In this case, we have almost all the necessary elements to replace damaged or missing parts.

  • The pinout of the microcircuits does not correspond to the required location.

Sometimes you come across devices where the microcircuits are located incorrectly. For example, they are rotated 90 or 180 degrees. What is the threat? At best, the device will not work. At worst, an incorrectly soldered microcircuit will fail. In the worst-case scenario, an improperly soldered microcircuit will burn out and break other microcircuits and, quite possibly, PCB tracks. Therefore, if we see that the microcircuits in the device were soldered by the previous masters, we carefully look to see if they are correctly located before supplying power to the multimedia device.

  • PCB tracks damage. PCB deformation.

Perhaps the most unpleasant and difficult cause of the malfunction. It is necessary to look for a broken track if the reason was caused by deformation of the board due to improper removal and handling of it. If the place of damage immediately catches the eye, for example, in the place of mechanical damage, there are no problems with the repair. If somewhere in an unknown place on the board there is a microcrack, especially in the inner layer, then this will be the most difficult repair that can only be imagined. But we know the main places of microcracks caused by the deformation of the board and, when detected, we eliminate them.

  • Incorrect programming and en

Many repairmen neglect to update all modules or at least the main ones. Since, for example, updating all five CCC modules requires an average of about 2 hours. Secondly, to update a device without a car you need a bench, and without a bench not one really wants to sit in a car for 2 hours with an external charger connected and control the update process. Thirdly, if you use Chinese cheap diagnostic equipment during the update, the connection can easily be cut off, which will lead at best to a second attempt to update, and at worst to a second repair. Therefore, the masters prefer not to take risks once again, but to hope that during the warranty period that they give, the FLASH will not malfunction due to the loss of charge in the gates of the transistors and they will not have to repair the device again for free under warranty. It is an unacceptable for us to give a 15-month warranty and refuse to update, if possible, all microcircuits containing non-volatile memory in a device; therefore, we rewrite all FLASH and EEPROM memory cells possible. The following are the main causes of incorrect programming and encoding that we had to deal with and eliminate:

  • If you have the Top HiFi Individual (option 752) amplifier installed, and your multimedia device was encoded with the 677 Top HiFi option, then the maximum volume (especially with a bass) will be noticeably lower. If the situation is the opposite, then at maximum volume the sound will interrupt, which may serve as an incorrect diagnosis of the performance of your Top HiFi amplifier. As a result, this leads to an attempt to repair an amplifier that does not require repair due to incorrect encoding.
  • Joystick malfunction;
  • Disappearance of the “Services” menu;
  • Disappearance of “even waves”;
  • Loss of parking sensors or rear view cameras;
  • Loss of the “Navigation” menu;A warning massage that you need to move carefully every time the ignition is turned on;
  • Losing the ability to start an autonomous heater with a timer;
  • Etc.
  • Damage to flexible cables.

Non-professional repairmen very often break FPC/FCC connectors for connecting flexible cables, and especially smart ones even manage to severely damage the cable itself. We always have new cabels that replace the damaged ones.

  • Flexible cable connectors damage.

FPC/FCC connectors are often broken by inexperienced repairmen. But we are ready for such troubles and we always have new connectors that we install instead of the damaged ones.

  • Failure of the optical converter of the MOST bus

The same inexperienced repairmen often break the plastic mounts of the optical transceiver on the MOST bus. In this case, we had to approach this problem creatively and come up with a special device that allows us to reliably connect optical cables with an optical transceiver with damaged fasteners. We print this device on a 3D printer using ABS plastic. This does not affect the cost of repairs.

  • Breakage of the edges for the screwdriver at the screws. Breakage of the thread for the screws. No screws.

Quite often, repairmen tear off the edges on the screw heads, they also tear off the threads in the aluminum case, due to the fact that they do not know about the force that needs to be applied when tightening the screws. Usually they also use the wrong tools. It is also not uncommon for these masters to tighten not all the screws and leave empty holes. This can lead to an increased vibration amplitude of the circuit; as a result, microcracks may appear in the soldering points. This will cause the device to stop working. If we see damaged or missing screws, we install new ones. In the case of a breakage of the thread in the aluminum case, we use screws with a slightly larger diameter thread.

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