1、速腾车点火线圈爆裂 Sagitar’ignition coil burst
故障现象 The fault phenomenon：
客户反应汽车严重抖动，加速无力甚至熄火，同时伴随ASR防侧滑灯点亮。From customers reaction that the vehicle has severe dithering in the driving, and cannot Accelerate even flameout. Also the ASR anti-slide light up.
用VAG5052A查询故障：Using VAG5052A for querying failure:
Engine electronic system: The first of ignition coil starts the positive terminal gets short circuit.
03制动电子系统：发动机电子系统故障 Brake electronic system: Engine electronic system failure
44电子助力转向系统：发动机电子系统故障 Electronic power steering system: Engine electronic system failure.
Because they belong to the system on the power line, through the gateway linked together to share the information on the power bus, any part of the bus failure, in other systems will be based on pre-set procedures to record fault information. It is tentatively judged that the failure of the brake electronic system and the electronic power steering system is caused by the engine failure, and the inspection of the engine failure is focused. By the engine fault code, suspect the problem in the ignition coil or its line.
Starting the engine, idle for about 10 minutes, the vehicle has severe dithering in the driving, and cannot speed up even flameout. Also the ASR anti-slide light would light up. And then restart the vehicle, the engine can run normally, with VAG5052 read the engine data stream 14 group, this time the data are normal. Fire memory when failure occurs again. The fault points are judged on the ignition coil, ignition coil line, or engine control unit.
拆下二次空气泵，拔下点火线圈的插头，检查插头内没有锈蚀，用万用表测量点火线圈的四根线，Ｔ４/2有12V正电，T4/4对地通。T4/1 , T4/3到发动机电脑J361的T121/112,T121/113连接正常。拆下点火线圈，发现点火线圈的底部有裂纹，于是更换点火线圈，重新试车，故障没有出现。到此问题似乎解决了，但过了不久，故障再次出现！而且发动机无法启动了
Removing the secondary air pump, and remove the plug of the ignition coil, checking that there is no rust in the plug, measure the four lines of the ignition coil with the multimeter, and the t4/2 has 12V positive, and t4/4 to the computer J361, T121/113 connect normal. The ignition coil was removed and a crack was found at the bottom of the ignition coil, so the ignition coil was replaced and the vehicle was retested. Failure did not occur. The problem seems to be solved, but after a while, the failure reappears! And the engine failed to start.
At the station, the ignition coil was found to be explosive again. It seems that the problem is not in the ignition coil, but in the wiring or engine control unit that relates to the ignition coil. Re-examine the line of the ignition coil. (figure 1)
点火线圈的二号针脚接的是从J363(SIMOS控制单元供电继电器)经过SB14保险丝过来的12V正电; 第一和第三针脚接的是J361（发动机控制单元）的控制端，其中一号脚控制一四缸的点火，三号脚控制的是二三缸的点火。就是说，发动机正常工作时，当一缸在压缩上止点时，J361会断开一号脚的接地，从而在一四缸的次级线圈产生感应电压，点燃一缸混合气，一缸作功。测量一三脚到J361线路，正常。参照电路图可以看出：点火线圈的接地线也是曲轴箱通风加热电阻N79的搭铁线，N79的一号针脚接的是从J519（中央电器控制单元）经过SC29保险丝过来的12V正电。微信公众号 汽修技术服务 试想，如果642搭铁点搭铁不良，J519的正电会经过N79直接和点火线圈的四号针脚相连，这样点火线圈的初级回路就被阻断，造成无法点火，发动机控制单元J361会记录点火线圈对正极短路故障。检查642搭铁线，在发动机空气滤清器下面，发现642搭铁点的固定螺母已经松动。清理搭铁点，重新固定好，换上新的点火线圈。为了验证故障点，清除故障码，启动发动机，人为断开642搭铁点，故障出现，证明故障点就在642搭铁线松动。
The second pins of the ignition coil comes from the J363 (power relay of the SIMOS control unit) through the SB14 fuses and produces the 12V positive Voltage. The first and third pins are controlled by J363 (engine control unit), one of the which controls the ignition of a four-cylinder, the second and third cylinders are controlled by the third pins. This is to say, the normal of the engine, when the first check point on the compression, J361 would disconnect, thus induced voltage in the secondary coil of matters cylinder, lit a crock of mixture, a crock of doing work. Measure the first and the third cylinder to J361 line, it shows normal. Reference to the circuit diagram can be seen: the ground line of the ignition coil is also an iron wire of the crankcase, and the one on the N79, and the one on the N79 is from J519, which is the 12V positive charge from the sc-29 fuses. Wechat public motor repair technology services, just thinking, if 642 iron points were not fit, the positive charge of J519 would be connected directly with the fourth stitching of the ignition coil at N79, so that the primary loop of the ignition coil would be blocked and the ignition coil would not be ignited, and the engine control unit J361 would record the ignition coil to the positive terminal short circuit fault. Check the 642 for the iron wire, under the engine air filter, find that the fixed nut of 642 iron point has been loosened. Cleaning up the iron point , reattach and replace with a new ignition coil. In order to verify the failure point, remove the fault code, start the engine, and manually disconnect 642 to the iron point, the fault occurs, and the fault point is found to be loose in 642.