ECU code is a trigger data of in-vehicle unit. Each control unit has a relevant code, and the same model has different configures and codes. For example, the codes for two airbags are different form that for four airbags when installing. If you programme the code of two airbags installed to the control unit of four airbags, the two airbags may not be triggered.
When need to code control unit? After installing control unit, “Control Unit Code” may be stored in ECU, but you should perform coding operation again. If you don’t do that, vehicle running malfunctions may be present, such as accelerating fault, in-gear malfunction, and engine rough running. Malfunction indicator is off when these occur. You can not check trouble codes through a scanner. Please check if ECU code is error. Trouble code will cause: bleeding value high and shifting impact, enlarging A/T load,the implausible trouble codes are stored in malfunction memorizer.
More Launch X431 Test Case check here:How to use Launch X431
Operation on coding ECU:
1.Select systems, e.g. ABS、AT、SRS.
2.Enter “Coding ECU” menu;
3.Enter code( normal for 5 digits);
4.Click “OK” then a prompt “ coding successful” will pop up;
5.Close key and save the memory value.
Precautions on coding:
1.Before changing ECU, please connect the faulty ECU with X431, and enter reading ECU information function, record or print the ECU code, such as 04502, and number of the ECU parts,
such as 06A906033. When you buy a new ECU from the franchiser, you should provide the details
of vehicle. Sometimes you buy it via the number of parts only, so the provider may sell you the
incorrect module. You can not programme it. Make sure that the number of new parts is the same as the old. And the code for new module is 00000, you can programme it.
2.A prompt “Coding Successfully” will pop up, but this does not mean coding has been completed.Close key after prompting “Coding Successfully”. Save the data in ECU.
3.If coding failed, check the system is normal or not, the code is correct or not, and the number of parts is the same as the factory default.
4.The code is normally 5 digits, and sometimes 7 digits.
Code for VW（only for reference）
Model, system, code
Santana
System Code
01 Engine system 08001（old model）、04001（new model）
03 Brake system 04505、00000、03604、01091、02802
15 ABS 12878
AUDI
System Code
01 Engine system 04002、04502、06252、04552
02 A/T 00004、00013
03 Brake system 00022、00021、06169、00031
17 Instrument Cluster 00144、07262、00162、00062
08 A/C heat system 00160、00140、00060、00061 （America）
15 ABS 00004、00204、00106
35 Central locking system 06731、04683、00001
66 Seat/mirror adjustment 01106、00106
PASSAT B5
System Code
01 Engine system 04502,04097
15 ABS 22599,12364(China),00065,00066,00067(America)
03 Brake system 03604
JETTA
System Code
01 Engine system 00001（2 valves）、04000（5 valves）
03 Brake system 01901（2 valves),03604（5 valves）
15 ABS 02610(double airbags),02611(single airbag),65535(general code),00065
POLO
System Code
01 Engine system 00017、12878
03 Brake system 0001097
09 ECU 25612
15 ABS 12343
17 Instrument Cluster 00141
19 Gateway CAN bus 00014
44 Steering power system 10140
46 Central module 00064
56 Radio system 00001
BORA
System Code
01 Engine system 26500、26530
03 Brake system 0001025、0021505
15 ABS 12875
17 Instrument Cluster 01102、05122
19 Gateway CAN bus 00006
46 Central module 00259
GOLF
System Code
01 Engine system 00033
02 A/T 00000
03 Brake system 01025
15 ABS 12855
17 Instrument Cluster 00259