TEST 2: Testing The M1 Blower Speed Circuit
If you've reached this point, you've made sure that your 3.0L Ford Ranger's vent selection control switch is working in TEST 1. Our next step is to test the medium one (M1) speed circuit.
Like in the previous test, will be using an automotive 12 Volt test light on the blower resistor connector to find out if the M1 circuit is OK.
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. - 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 test result confirms that the blower motor switch's M1 circuit is OK on your 3.0L Ford Ranger (Mazda B3000).
So far so good. The next test is to test the M2 blower motor speed circuit. 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 result confirms that the blower motor speed switch, on your 3.0L Ford Ranger or Mazda B3000, is defective and needs to be replaced with a new one.
TEST 3: Testing The M2 Blower Speed Circuit
In this test section, we're gonna' test the medium two (M2) blower speed circuit.
This test procedure is the same as the previous two tests except that we're gonna' be testing the number 3 terminal of the blower resistor connector.
If the test light does not come on, then you can conclude that the blower switch is defective.
Let's get started:
- 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. - 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 confirms that the blower motor switch's M2 circuit is OK.
Our next step is to make sure that the HI speed circuit is OK. Go to: TEST 4: Testing The HI Blower Speed Circuit.
CASE 2: The 12 Volt test light DID NOT turn on. With this test result you can conclude that the blower motor switch is defective and needs to be replaced.
