TEST 2: Testing The M1 Blower Speed Circuit
In the previous test, we made sure that the LO speed circuit was functioning correctly and by extension confirmed that the vent control switch is OK too.
In this test section, we're now gonna' make sure that the blower switch M1 circuit is functioning correctly.
We'll test this circuit just like we tested the LO circuit in TEST 1.
These are the test steps:
- 1
Place the AC/Heater Control Panel's vent selection control knob on any selection but OFF.
NOTE: The blower resistor and the blower motor must be disconnected from their electrical connectors on your 2.5L Ford Ranger (Mazda B2500). - 2
Connect the 12 Volt test light's alligator clip to the positive (+) battery terminal of your Ford Ranger's battery.
- 3
Select blower motor speed M1 on the AC/Heater Control Panel.
- 4
Probe the resistor block connector female terminal identified with the #1 with the metallic point of your 12 Volt test light (see photo above).
Female terminal #1 has a light green with white stripe (LT GRN/WHT) wire that connects to it. - 5
The 12 Volt test light should come on if the M1 circuit is OK.
Let's examine your test result:
CASE 1: The 12 Volt test light turned on. This is the correct test result and lets you know that the blower motor switch's M1 circuit is working correctly.
The next test is to check that the M2 speed circuit on your 2.5L Ford Ranger (Mazda B2500). For this test go to: TEST 3: Testing The M2 Blower Speed Circuit.
CASE 2: The 12 Volt test light DID NOT turn on. This test result lets you know that the blower motor switch is defective and needs to be replaced.
TEST 3: Testing The M2 Blower Speed Circuit
If you've reached this point, then you have confirmed that blower speed LO and M1 circuits are functioning correctly on your 2.5L Ford Ranger (Mazda B2500).
Now we're gonna' test the blower motor speed M2 circuit and make sure it's OK too.
These are the test steps:
- 1
Place the AC/Heater Control Panel's vent selection control knob on any selection but OFF.
NOTE: The blower resistor and the blower motor, on your 2.5L Ford Ranger (Mazda B2500), must be disconnected from their electrical connectors. - 2
Connect the 12 Volt test light's alligator clip to the positive (+) battery terminal of your Ford Ranger's battery.
- 3
Select blower motor speed M2 on the AC/Heater Control Panel.
- 4
Probe the resistor block connector female terminal identified with the #3 with the metallic point of your 12 Volt test light (see photo above).
Female terminal #3 has a yellow with red stripe (YEL/RED) wire that connects to it. - 5
The 12 Volt test light should come on if the M2 circuit is OK.
Let's examine your test result:
CASE 1: The 12 Volt test light turned on. This is the correct test result and lets you know that the blower motor switch's M2 circuit is working correctly on your 2.5L Ford Ranger (Mazda B2500).
The next test is to check that the HI speed circuit. For this test go to: TEST 4: Testing The HI Blower Speed Circuit.
CASE 2: The 12 Volt test light DID NOT turn on. This test result lets you know that the blower motor switch is defective and needs to be replaced.
