TEST 2: Testing The Blower Switch Speed 2 (M1) Circuit
In this test section, we're gonna' make sure that the speed 2 (M1) circuit is OK within the blower motor control switch.
The wire that we're gonna' test is the light green (LT GRN) wire of the blower resistor's electrical connector.
The LT GRN wire is identified with the number 4 in the photo above.
If the speed 2 (M1) circuit is OK (in the blower switch), the 12 Volt test light should light up.
If the speed 2 (M1) circuit has a problem (in the blower switch), the 12 Volt test light will NOT light up.
These are the test steps:
- 1
Disconnect the blower resistor from its electrical connector.
- 2
Select blower motor speed 2 on the AC/Heater Control Panel.
- 3
Connect the 12 Volt test light's alligator clip to the positive (+) battery jump start terminal in the engine compartment.
The positive (+) jump start terminal is on the under-hood fuse box (see photo 2 of 2 of TEST 1). - 4
Back probe the terminal that connects to the LT GRN wire of the resistor block's connector with the metallic point of your 12 Volt test light (see photo above).
NOTE: Avoid probing the front of the female terminal of the connector or you run the risk of damaging it with the tip of the 12 Volt test light. - 5
The 12 Volt test light should come on if the speed 2 (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 control switch's speed 2 (M1) circuit is OK.
The next test is to check that the speed 3 (M2) circuit. For this test go to: TEST 3: Testing The Blower Speed 3 (M2) Circuit.
CASE 2: The 12 Volt test light DID NOT turn on. This test result lets you know that the blower motor control switch is defective and needs to be replaced.
TEST 3: Testing The Blower Switch Speed 3 (M2) Circuit
The wire that connects to the speed 3 (M2) circuit inside the blower switch is the light blue (LT BLU) wire of the blower resistor assembly's connector.
The LT BLU wire is labeled with the number 3 in the photo above.
If the speed 3 (M2) circuit is OK (in the blower switch), the 12 Volt test light should light up.
If the speed 3 (M2) circuit has a problem (in the blower switch), the 12 Volt test light will NOT light up and you can conclude that the blower switch is bad and needs to be replaced.
These are the test steps:
- 1
Disconnect the blower resistor from its electrical connector.
- 2
Select blower motor speed 3 on the AC/Heater Control Panel.
- 3
Connect the 12 Volt test light's alligator clip to the positive (+) battery jump start terminal in the engine compartment.
The positive (+) jump start terminal is on the under-hood fuse box (see photo 2 of 2 of TEST 1). - 4
Back probe the terminal that connects to the LT BLU wire of the resistor block's connector with the metallic point of your 12 Volt test light (see photo above).
NOTE: Avoid probing the front of the female terminal of the connector or you run the risk of damaging it with the tip of the 12 Volt test light. - 5
The 12 Volt test light should come on if the speed 3 (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 speed 3 (M2) circuit within the blower switch is OK.
The next test is to check that the speed 4 (HI) circuit. For this test go to: TEST 4: Testing The Blower Speed 4 (HI) Circuit.
CASE 2: The 12 Volt test light DID NOT turn on. This test result tells you that the blower switch is bad and needs to be replaced.
