Install the ignition switch in position of ON.

Include a heater of back glass.

Fig. 7.90. Check of thread of heating of back glass

ATTENTION The contact of thread of heating of back glass with the probe of a tester can lead to thread damage. Wrap up aluminum foil around the end of the probe and check thread, concerning its foil (fig. 7.90);

Fig. 7.91. Connection of the probe of a tester to the ends of thread

Connect the positive probe of a tester to the positive end of each thread, and the negative probe to the mass of a body (fig. 7.91);

Moving the positive probe from the positive end of thread to negative be convinced that tension decreases respectively.

If tension changes quickly, thread is faulty. Repair thread.