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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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BMW engine temperature

BMW engine coolant temperature сorrector

Hello!

Everyone knows the problem of fairly modern BMWs, and I think not only BMWs. The problem is the boiling of the engine to 108 degrees Celsius at low loads (such as traffic jams, waiting in a parking lot, etc.). The cycle is simple – when temperature reaches 108C, ECU resets the temperature to 105 by turning on the fan (in winter it doesn’t even turn on sometimes) and the electric pump to higher speeds, and then again in a circle.

Of course, when you start driving actively, the coolant temperature drops harshly and the oil temperature drops next. Obviously, it is dangerous to accelerate on an overheated ICE. Therefore, engineers have made a safer engine cooling cycle at power mode. A high operating temperature of an ICE means high pressure in the coolant system, oil coking due to overheating, low pressure in the oil system due to overheating of the oil, and many more reasons. These reasons are described in many places and many people have encountered them. It is clear that there are no critical values, but why should we risk.

My coolant reservoir exploded when I was just in the parking lot. I was watching how the oil temperature arrow for 30 minutes rises from 105 to 110 degrees. I changed the lid of the reservoir 4 days before. I am sure that if the coolant temperature was 85 degrees, this would never have happened.

Cold thermostat

This is a dubious decision for N54 / N55 engines, since there is an electric pump and if the thermostat opens earlier than necessary, the system will not turn on and the liquid will flow sluggishly through the radiator with practically no cooling and, of course, without cooling the engine.

There is an effect from it. It reduces the temperature in traffic jams by an average of 5-10 degrees (I collected feedback from the people who installed it).

Additional radiator

They install it for hot countries. Information from unverified sources says that there is a slightly different firmware, and this firmware regulates the temperature modes of the engine in a different way during operation.

There are too many problems for me. Therefore, I have discarded this option.

BMW engine coolant temperature сorrector

This is what the manufacturer calls it 🙂

Outwardly, it’s just a weird thing. But at the same time, it’s well built! It’s very easy to install in the engine and this thing becomes invisible for a layman. It uses factory connectors everywhere, and the wires tucked into a black cable duct.

You install the device on the upper hose of the radiator. It connects in-between the native temperature sensor. One end to the ECU, the other end to the DME. This solution is very convenient. Simple and efficient.

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BMW engine coolant temperature corrector

On modern cars, the following cooperatively working devices achieve temperature control:

Controlled thermostat
Radiator cooling fan
Radiator shutters
Variable displacement pump

DME activates all of them when the coolant temperature approaches 108-110 degrees. Alltogether, and not each separately. In contrast to the classic cold thermostat: when it is open, the cooling fan is off, and there is no point in this (purely academic case, in practice, a cold thermostat on “hot” firmware is really useful).

If we talk about good cold firmware, then it must correctly manage all the listed components. In other words, chip makers must intervene in the operation of important operating modes of engine components. Therefore, I have great doubts about the existence of such a firmware.

Now about the BMW engine coolant temperature corrector. As I already wrote, all engine temperature control mechanisms are activated when the coolant reaches the upper temperature threshold. According to the algorithm specified by the manufacturer in the DME. The thermostat corrector only shifts this threshold down by 12-15 degrees and does not affect anything else or interfere with the operation of other devices.

The point is this: increasing the transmitted temperature from the sensor to the system within 15 degrees. What does it do? Cooling fan turns on; electric pump works more intensively (if you have such option). The temperature seen by the system is corrected (shift upwards by an average of 15 degrees). Now, through the hidden menu, the average temperature is 110 degrees, but in fact, it is 95.

When the temperature reaches 93-95 degrees (in my case), this device corrects sensor readings by 12-15 degrees. In the 7th test, you can see a surge in readings. Starting from a certain point, we see that the temperature is 12-15 degrees higher than it actually is. The entire cooling system starts to operate at a lower temperature and operates normally. More information can be found on the internet.

I think this option is excellent, and I see no arguments against it. This is a ready-made, tested product for good money. Surely, this can be implemented through an engine firmware update, but not all engines have it. For myself, I chose this method, it seems to me simpler and more practical, and the installation of the device takes 15 minutes. You can remove the device at any time by yourself.

I’ve been driving with the BMW engine coolant temperature corrector for about 2 months now. No problems at all. The oil temperature dropped and in urban conditions, it is about 100 degrees Celsius. I don’t see real readings of the coolant temperature, apparently, it dropped by the same 12-15 degrees.

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Checking the electric fan with ECU at Peugeot & Citroen (PSA) without connecting to the car.

In order to check the electric fan with an ECU without a car, you need:

  1. First you need to measure the resistance between Signal and + Ubat (K.30). It should be between 1.5 kOhm and 2.5 kOhm. If the resistance is less than 1.5 kOhm or more than 2.5 kOhm, then this indicates that the fan is defective, or its life is coming to an end, despite the fact that it can still work for some time. When measuring the resistance between Signal and + Ubat (K.30), nothing must be connected to the fan except a measuring device!
  2. Next, you need to apply a 12 V supply voltage from the battery or power supply to the +Ubat(K. 30) and GND (K. 31) contacts of the power connector, designed for a maximum current of at least 30 … 50 A (depending on the type of fan).
  3. If there is a relay on the harness, then to turn it on, connect the + Relay input to + Ubat (K.30). And for a 4-pin connector, connect the -Relay input to GND (K.31).
  4. For CITROEN C3, you also need to drop +12 V to the Ignition input.
  5. If +12 V is applied to the Signal input or nothing is connected (left in the air), then the fan should gradually spin up to maximum speed.
  6. If mass (GND) is applied to the Signal input, the fan should stop completely.
  7. To smoothly change the speed, a pulse PWM signal with a frequency of 100 Hz must be applied to the Signal input.
  8. In order to check the Diagnostics output, connect a 10 kOhm resistor between + Ubat (K.30) and Diagnostics, and also connect a voltmeter between GND (K.31) and Diagnostics.Then apply 12 V to the contacts of the power connector + Ubat (K.30) and GND (K.31) from a source designed for a current of 30 … 50 A. Connect Signal input to +12 V or nothing. After the fan starts to spin up, measure the voltage between GND (K.31) and Diagnostics, it can gradually increase from 0 V to 1 V at the maximum fan speed. If the measured voltage exceeds 1 V at the maximum speed of rotation this will cause an error related to the fan malfunction recorded in the engine ECU. This error may cause the fan to work incorrectly or not start at all. But with this error, the fan can be started forcibly (as described above) or using the diagnostic program on the car itself.

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BMW THERMOSTAT PROBLEM

BMW thermostat problem

Since 1996, BMW began to install a controlled thermostat with an opening temperature of 105c on gasoline cars (as an example: thermostat 11537586885 for engine BMW n62, n63, n73, n74, s55, s63; thermostat 11537509227 for engine BMW m52, m54, m56; thermostat 11531436386 for engine BMW m62). Since then, the so-called BMW thermostat problem has been haunting these cars, because of the high operating temperatures, the wear and rapid failure of all engine units have sharply increased, as well as of the automatic transmission and exhaust system catalyst. For this reason, performance cold thermostats 11537586885, 11537509227, 11531436386 for BMW with an opening temperature of 90C appeared.

There is a strictly defined operating temperature for the engine that provides optimal working conditions. As a rule, within 90C. At lower temperatures, the engine oil does not have sufficient fluidity, which means that its resistance increases when the pistons move. At higher temperatures
– engine overheating (as an example, the above-mentioned BMW engines. One of the most common is n62, where the thermostat 11537586885 was originally installed with an opening temperature of 105c, not 90c).

The cooling system is designed to maintain an optimal operating temperature: when starting the car, you need a quick warm-up, and then, in the process of driving, you need high-quality cooling.   The thermostat takes over the regulation of this process, which is installed at the “fork” between the large and small circle of the cooling system and controls the direction of the coolant flow.

Until the engine is warmed up, the thermostat closes the pipe to the radiator, directing the coolant to a small circle: from the motor jacket, through the thermostat, bypass channel and back to the engine. Antifreeze does not pass through the radiator and does not cool, allowing the motor to warm up faster.

When the engine warms up to operating temperature (usually 90s), the thermostat opens the valve leading to the radiator, and the antifreeze begins to cool itself and cool the engine. Depending on the temperature of the antifreeze, the thermostat can close the valve to the bypass channel completely (when the engine needs intensive cooling) or partially.

Thus, the thermostat in a completely autonomous mode regulates the amount of antifreeze entering the cooling radiator, to keep the engine temperature at a constant operating level. On modern cars, thermostats can be equipped with an additional temperature sensor and heater (such as BMW thermostats 11537586885, 11537509227, 11531436386), paired with an electronic control unit. At medium engine speeds, the coolant temperature is maintained at a higher level (BMW thermostat problem), and at maximum load, additional heating is turned on, and the thermostat is triggered earlier, which allows you to reduce the temperature of the antifreeze by about 10°C. This decision can be controversial, since over time, the additional heater may fail.

Thermostat malfunctions: signs, causes, consequences.

Scale on the stem, corrosion on metal parts. As a rule, deposits in the cooling system appear due to poor-quality antifreeze and untimely replacement. Scale on the thermostat parts makes it difficult for the stem and valves to move, after that, the thermostat stops responding correctly to changes in the coolant temperature.

Failure due to vibration. More often, this problem happens with defective or low-quality products, in which the joints and connections are not sealed enough. If the copper cylinder is not sufficiently sealed, coolant will enter and prevent the thermostat from operating.

Destruction of the rubber seal due to high temperature. Overheating can disable the already “tired” rubber, after which it forms cracks and leaks. The membrane inside the working part (between the wax filler and the stem) also suffers from overheating.

If the thermostat breaks down, it begins to respond worse to temperature changes, and then it jams. The thermostat valves may block the pipe leading to the radiator or to the bypass channel, or they may stop in the middle position.

Malfunction signs:

The engine heats up for a long time – the pipe to the radiator is open, the antifreeze is cooled, preventing the engine from warming up.

The engine overheats (arrow is in the red zone) – antifreeze does not get to the radiator.

The engine heats up longer than usual, and under load the temperature rises sharply – the valves are stuck in the middle position, part of the coolant constantly passes through the radiator, but at intense driving this cooling is not enough.

Also, indirect signs of a thermostat failure may be non-working interior heating (the”stove” blows cold air, increased fuel consumption, deterioration of engine dynamics.

The worst consequence of a thermostat failure is engine overheating: in the heat, a few minutes are enough to bring the engine into emergency condition.  But driving with an insufficiently warmed engine affects its resource: wear of parts increases, engine oil works ineffectively.

How to check the thermostat?

  1. Start the engine. Before it warms up to operating temperature, antifreeze should not enter the radiator. Consequently, the pipe leading to the radiator must be cold. If it is warm – antifreeze enters the radiator ahead of time.
  2. When the engine warms up, the coolant should go to the radiator, the pipe should be warm.The engine is warmed up, but the antifreeze does not go to the radiator – the valve is closed.
  3. If the engine is well warmed up (almost to the red zone), the antifreeze should not enter the bypass pipe, but all pass through the cooling radiator. Accordingly, the pipe to the radiator will be hot, and the bypass pipe will be cold.

Another test method recommended by old-school car enthusiasts is to dismantle the thermostat and test it in hot water. Of course, if you wish, you can also evaluate the operation of the device, only you need to monitor the opening temperature of the valves. But if there are complaints about the operation of the thermostat, it is better to simply replace it. Thus timely installed performance cold thermostats 11537586885, 11537509227, 11531436386 for BMW engine n62, n63, n73, n74, s55, s63, m52, m54, m56, m64 with an opening temperature of 90C, will help to significantly save money in the future and solve the BMW thermostat problem.

https://electrorefit.com/product/cold-thermostats-for-petrol-engine-bmw/