In this entry – experience and conclusions, using such alternative alternator for some 10 .. 15 motor hours.
In the beginning, I will mention the most extreme experience. I hope this case will persuade even the biggest skeptics that no “alternative” products CAN BE USED for such important hubs.
In the evening, when it was already dark, after starting to drive (when the speed of 40 and 50 km/h was reached), the car suddenly became a metal stack without any precursors. Everything turned off. With everything, I really mean EVERYTHING. The lightning of the KOMBI disappeared, CCC disappeared. The car lights turned off (everything – daylights, etc.). The engine turned off accordingly – the steering and brake power boosters disappeared. When I managed to stop the car, I discovered that also the central key is not working. Also, the car key mechanism was not working – I could not take out the key from the slot. The car was COMPLETELY dead.
In my case, this incident happened at low speed; at the town, I saw where I could stop the car. But imagine, what would happen, if such “performance” would happen on the highway? At night? On the road bend? In the situation when you have to break swiftly or perform a maneuver?
If after all this you will continue to claim that “by the idea, the alternative solutions can be used”, I would suggest for you to buy more expensive and better health and life insurance. I have no other advice left.
But, let’s come back to my adventure. After stopping the car, I was in a hurry to open the engine hood. My first taught was – the rectifier of the alternator is damaged; it gives the short-circuit. Now we have to check if the wires are not starting to burn; flames should be suppressed; the battery should be disconnected. Below the engine hood were no signs of burning; the temperature of the alternator’s body was correct: 60 .. 70 oC. I didn’t even open the battery compartment when the car came back to life. The daylights came to life; I was able to start the engine without any problems. No symbol was light up in KOMBI. ISTA did not indicate any new error message in any module!
What had happened? The situation on a large scale was explained by the INPA data log, which was turned on at that moment. During the last seconds before the complete crash, the data of the alternator were looking like this:
a) the fake temperature reading was very untypical: 16oC. This is a mega-rare reading; I don’t even remember when I would previously have seen anything like that;
b) the alternator indicated that the developed charging current: 38A;
c) the values of required (14.6V) and confirmed (14.7V) voltage of the alternator are not corresponding;
d) the engine has worked in Overrun mode, ”leftover” around 6.8A;
e) the onboard voltage has suddenly dropped to 11.5V.
Yes, there are fundamental contradictions in these alternator data. If someone would ask me, how is that possible: the alternator claims that it charges with a high current (part of this is even a leftover), but the onboard voltage drops swiftly and significantly, I would answer – obviously, some fundamental problem in the high-power electricity supply. For example, previously mentioned damage of the alternator’s rectifier. Short-circuit on the main plus wire. Damage of the main current wires in such a way that somewhere mystically, some 1kW or energy disappears – obviously, the burning has already started there. Yes, in such a situation, to save the car’s electronic: rough, but a survival solution – turn off completely everything!
I really hope you will remember this experience and reduce the desire to “save” on BMW’s repairs.
In continuation – what more observations I made. I addition to the defect mentioned in the first part of the entry:
First – the alternator doesn’t support few more advanced working modes. As a result, some of the required management modes tend to switch off the charging in stationary driving conditions, which is not idle. Accordingly, the city drivers will not even notice this problem – whenever the idle is restored (even for a short time), the alternator restores the charging.
Second – the alternator has gross software bugs; it regularly, for approximately a second, uncontrollably develops a full power. Such happenings are often, around 1 time in a minute.
Third – obviously, the mechanism of problems with overvoltage, described in the first part of the entry, was following. When driving on the highway, the alternator, who did not “know” the current requested work mode, has switched off the charging. For a longer period of time, the battery was discharged, its internal resistance increased. When switching the gears (in all cases of the crash, this was performed), the alternator restored the charging. Still, the short-term uncontrollable current spike gave a rapid voltage increase in the electrical system. The battery in this situation could not resist because it was discharged.
Fourth – DME regularly checks the alternator’s work in different modes and adapts its load indications. With this alternator, all these tests failed (it could be seen very well). As a result, DME turned off intelligent management, switched to the method of fixed voltage and cars of the previous generation. The most interesting part – in DME (and other blocks) was NO error messages regarding the alternator’s performance!
At the same time, the IBS system data shows that (during the last two days, when the car was used) both data of SOC and the energetical balance are faulty:
Actually, this is a confirmation that many users’ claims that “everything is fine with this alternator, there are no error messages” are true. There really could be no error messages! Simultaneously, the IBS system is not working; the idle management system of the engine is not working. And additionally to everything – there can happen the excess, in a result of which the car on the road turns to the pile of metal for a moment, or its electronics are damaged due to overvoltage! An excellent product!