56
3.3.11
Variable speed cooling fan
At present, most cars' fans are variable-speed, and the speed of the fan can be adjusted according to different working
conditions and temperatures.
Use a BNC to banana cable, connect one end to channel 1 of the oscilloscope, ground the other end of the black
plug, and use a needle to pierce the red connector into the signal wire of the fan terminal; use a current clamp,
connect one end to channel 2 of the oscilloscope, and clamp the other end to it Pay attention to the direction of the
current on the fan's power cord. (If you need to test the current, connect a current clamp).
Use ATO oscilloscope to test the cooling fan, the specific operation is shown in Figure 3-37:
Figure 3-37 Variable-speed Cooling fan test
The following picture is the actual measurement diagram of the cooling fan of a certain model:
Summary of Contents for ATO1000 Series
Page 1: ......
Page 2: ...Version Info Version Date Remarks V1 0 2020 06 ...
Page 52: ...Chapter 3 Automotive Test 49 Figure 3 30 Electronic fuel pump test ...
Page 71: ...68 Figure 3 49 K line test ...
Page 79: ...76 Figure 3 57 Mazda 6 Cylinder internal pressure measurement ...