A new energy owner dragged the car to my shop. He had no choice: “teacher, the car was driving suddenly without power, and the dashboard reported `the electrical controller'. 4s says the power control's broken. More than 20,000 for one. My second-hand car is worth 30,000
I asked him, "did the 4s store say what was broken?"
"just say the internal malfunction of the controller, in exchange for total failure, not individual repair."
I unplugged the shell of the electric controller and measured the internal igbt module one by one. One of the igbts was found to have crossed the short road, but the others were intact. And i told him, "this can be fixed, and it doesn't have to be. The replacement of the igbt module, the cost of several hundred pieces of materials, plus maintenance hours, will be within 2,000 hours.”
He's not sure, but let me try. Fix the load, power's back up and the failure lights are out. He saved almost $20,000 and was so happy he almost invited me to dinner。
Many car owners do not know that the electrical control system (the electric controller) is the component of the “triple power” of the new energy truck that is most likely to be “imprisoned”. 4s suffered electrical failure, and the first reaction was a “turn to total”. Because it is always simple and profitable, maintenance is too complicated and the technical threshold is high. Today, the common failures of the electrical system and the idea of maintenance have been made clear to save you money。
I. What's the electrical system? Why is it so expensive
The electric controller (mcu) is one of the "brain" of the tram. It transforms the battery's direct current into communication power, driving the power. At the same time, it controls the turn and twist of the electric power, which corresponds to the “engine + speedbox computers” of the oil truck。
Prices for total electricity control: ordinary domestic vehicles (e. G., biadiène, eans) with total new electricity control of $5,000-$10,000. Medium-high-end vehicles (e. G. Pyramid p7, teslamodel 3) for 15,000 to 25,000 yuan. Luxury vehicles (e. G. Es8, bmwix3), $25-40 million。
The offer for 4s is usually double the price for accessories. This is because of the cost of profits, working hours and supplies. So many of the drivers heard the quotes and they just freaked out。
However, many of the internal malfunctions in the electrical control system can be repaired and do not require a total replacement. The 4s shop was not fixed, not because it could not be repaired, but because they did not earn money。
Ii. Common malfunction i: igbt module penetration (most common, repairable)
Igbt is a large power switch element within the electrical control and is responsible for “cutting” direct current electricity into communication. It operates in harsh conditions: high voltage (hundreds of volts), large currents (hundreds of ampere), high frequency switches. It's been a long time. It's possible to hit short roads or open roads。
Symptoms: unable to move, reported “wire control failure”. In serious cases, high-pressure fuses are melted and the vehicle is cut off。
Maintenance programme: dismantling the controller's shell and finding damaged igbt modules. Welding of new modules with hot wind guns or specialized tools. Re-paint thermal silicon, assembly test. Materials cost hundreds to one thousand depending on the igbt type and quantity. It's a thousand hours. The total cost is about us$ 2,000-3,000. The total offer could be 12,000。
Risk: specialized electronic maintenance capacity is required and not available at common repair plants. Poor repair may damage other components. But the success rate is high if you find a scalable specialty。
This is the case for the owners of new energy sources, with the replacement of an igbt module, which costs less than 2,000。
Iii. Common malfunctions ii: aging of the capacitor (maintainable)
There are large electrolytic capacitors in the electro-controlled interior for use in filtering and storage. When the electrical capacity is ageing, electrical control is unstable and can occur: accelerated contusion, power loss, energy recovery anomaly, high pressure alarm。
Maintenance programme: unplugging controllers and replacing ageing capacitors. It costs hundreds to hundreds of dollars and hundreds of hours. The total cost is within a thousand. However, electronic maintenance skills are required。
Iv. Common malfunctions iii: can communication failures (mostly software problems)
Electric control requirements and other vehicle-wide controllers (vcu, bms) communicate via can bus. Communications were interrupted and electrical controls were “unconnected” and vehicles were unable to move。
Reason: poor contact with communication lines (floating plugs, beam wear), damage to can chips inside controllers, loss of software program cards or data error。
Maintenance programme: inspection of wire beams and plugs; repainting or upgrading of electrical control software (which can be done at 4s stores); replacement of can communications chips (hundreds of dollars)。
Real case: “electron-controlled communication failure” by one of the publishers of the broad-air e ann vehicle, offering a total of $18,000. He went to the shop to examine it and found that one of the needles, which was an electrical plug, was corrupted and then returned to normal, at a cost of $100。
Common malfunction iv: fault of cooling system (electrically controlled fever)
The heat generated during electrical operations is high and requires cooling fluid circulation. Flows of cooling fluids, failure of pumps and congestion of pipelines can lead to overheating of electrical controls, triggering protection, limiting power or decommissioning。
Symptoms: “engine controller overheat” reported after long journeys; power drops; cooling fluids are low or often need to be added。
Maintenance programme: identification of cooling fluid leaks and replacement of seals or pipelines; replacement of electronic pumps (hundred to 1,000); clean-up of blocked heaters. It costs hundreds to 2,000. There's no need for a switch。
Why don't they fix the electric
Technical threshold high: electric maintenance requires equipment such as electronic circuits, welding, oscillators, etc. The repair technicians at 4s were mostly “replacement workers” and not “chip-level maintenance engineers”。
Plant policy constraints: many brands stipulate that internal electrical failure can only be replaced by total failure and that maintenance is not authorized. Responsibility for the damage occurred because of the lack of “original plant quality assurance” of the repaired components。
Profit-driven: in exchange for a sum, material costs plus working hours, mĀori may be in the order of 10,000. Fix an igbt for $2,000 and a few hundred. Which one do you choose
Risk: in the event of failure of maintenance, the electrical controls are completely scrapped and 4s is held accountable. It's better to make it easy and safe。
What are you going to do if the power is broken
First step: to confirm whether the electrical controls are faulty or peripheral. For example, cooling systems, lines, software. 4s stated that the “electrical control” was broken and asked them to provide the failure code and the basis for testing。
Step 2: ask if it is possible to repair it separately, without changing the total. 4s said, “can't fix it” and asked outside the shop. The online search "your car plus electric control maintenance" looks for a good shop。
Step three: if the vehicle is still in the quality assurance period, the manufacturer is required to claim compensation. Don't pay for it. 4s stated that it was “insured”, checking the date of purchase of the vehicle and the three packages of vouchers。
Step 4: if insured, the cost of repair and replacement is compared. Twenty-three thousand can be fixed, and it could be tens of thousands. Let's make a trade-off。
I'll tell you the truth
The owner of the car then drove for several months, and there was no more electrical problems. He said to me, "twenty thousand dollars saved, enough for years."
I told him, "the electrical system is not that fragile. Most of the faults are the failure of a small component, not the brain. But find someone who can fix it."
The tram “three power” was repaired and the water was deeper than the oil truck. The 4s store loves to switch. The roadside store can't touch the pressure. What you need is a teacher who knows high-pressure safety and electronic maintenance. It's not much, but you can find it with your heart。
Did your train call for electrical failure? How did you finally fix it? Let's share the comments and point the way to the other owners。
