How to solve the problem of light failure in the T7H vehicle of Sinotruk?

When Sinotruk’s T7H vehicle has a light failure failure,

■ The cause of the failure:

The left combination handle harness is off-line

The light switch harness is off-line

Circuit fuse blown

■ Tools for maintenance:

Special opening tool for multimeter and instrument panel

■ Failure inspection process:

1. Check whether the pin voltage of each gear of the light switch is normal;
2. Check whether the voltage of the low beam lamp of the combination switch is normal;
3. Check whether the ground wire of the headlight harness is tight;
4. Check whether the R106 and 120 resistors are properly assembled;

Note: Turn on the corresponding light position during measurement, and pay attention to avoid scratches when turning on the instrument panel.