Why is my blower control switch not working?
If continuity is not present where indicated in the test steps above and this lack of continuity coincides with the blower fan speed that’s not working on your pickup or SUV, then you’ve found the cause of the problem. Replace the blower switch in the A/C-Heater control panel with a new one to solve the problem.
How can I test the blower control switch?
One is to do a multimeter continuity test of the specific circuits that should be ‘closed’ when you turn the dial to the different blower motor speeds. The other, explained in TEST 2, is to bypass the blower switch and indirectly test the blower switch.
How to test the blower motor switch in Ford 4.0L?
CASE 2: All circuits tested had continuity where indicated in the test steps. This is good and is the correct and expected test result that tells you that the blower fan switch (in the A/C-Heater control panel) is NOT defective. Your next step is to bypass the blower resistor using a simple jumper wire.
What’s the speed of the blower motor switch?
This battery power is now diverted to terminal 3 of the blower switch harness connector (LT GRN/WHT wire). In tech speak: circuit 2 and 3 is now considered ‘closed’. The end result is that your Ford’s blower motor now runs in M1 speed.
One is to do a multimeter continuity test of the specific circuits that should be ‘closed’ when you turn the dial to the different blower motor speeds. The other, explained in TEST 2, is to bypass the blower switch and indirectly test the blower switch.
If continuity is not present where indicated in the test steps above and this lack of continuity coincides with the blower fan speed that’s not working on your pickup or SUV, then you’ve found the cause of the problem. Replace the blower switch in the A/C-Heater control panel with a new one to solve the problem.
CASE 2: All circuits tested had continuity where indicated in the test steps. This is good and is the correct and expected test result that tells you that the blower fan switch (in the A/C-Heater control panel) is NOT defective. Your next step is to bypass the blower resistor using a simple jumper wire.
How does the motor switch on a blower work?
The blower motor switch works by rerouting the current that passes through it from one internal contact to another. To be more specific, as you turn the blower speed knob… the blower switch ‘opens’ and ’closes’ two contacts.