Test Description
The number below refers to the step number on the diagnostic table.
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: HVAC Schematics Connector End View Reference: HVAC Connector End Views DEFINITION: The blower motor is inoperative in all speed positions. | |||
1 | Did you perform the HVAC Diagnostic System Check? | Go to Step 2 | |
2 |
Important: The mode switch must remain in any position except OFF throughout this diagnostic procedure.
Does the blower motor operate in any speed position? | Go to Blower Motor Malfunction | Go to Step 3 |
3 |
Does the test lamp illuminate? | Go to Step 4 | Go to Step 7 |
4 | Connect a test lamp between the blower motor supply voltage circuit and the high blower motor control circuit of the blower motor. Does the test lamp illuminate? | Go to Step 13 | Go to Step 5 |
5 | Test the high blower motor control circuit for an open, short to voltage or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 20 | Go to Step 6 |
6 | Test the blower motor switch ground circuit of the HVAC control assembly for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 20 | Go to Step 14 |
7 | Test the blower motor supply voltage circuit of the blower motor for an open, high resistance or short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 20 | Go to Step 8 |
8 |
Does the test lamp illuminate? | Go to Step 9 | Go to Step 15 |
Does the test lamp illuminate? | Go to Step 10 | Go to Step 11 | |
10 | Test the ground circuit of the heater blower relay for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 20 | Go to Step 12 |
11 | Test the heater blower relay ignition 3 voltage supply circuit for an open, high resistance or short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 20 | Go to Step 12 |
12 | Inspect for poor connections at the heater blower relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 20 | Go to Step 17 |
13 | Inspect for poor connections at the blower motor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 20 | Go to Step 18 |
14 | Inspect for poor connections at the HVAC control assembly. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 20 | Go to Step 19 |
15 | Repair the battery positive voltage circuit of the heater blower relay. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 20 | -- |
16 | Repair the ignition 3 voltage circuit of the HVAC control assembly. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 20 | -- |
17 | Replace the heater blower relay. Refer to Blower Motor Relay Replacement in Heating, Ventilation and Air Conditioning. Did you complete the replacement? | Go to Step 20 | -- |
18 | Replace the blower motor. Refer to Blower Motor Replacement in Heating Ventilation and Air Conditioning. Did you complete the replacement? | Go to Step 20 | -- |
19 | Replace the HVAC control assembly. Refer to Heater and Air Conditioning Control Replacement . Did you complete the replacement? | Go to Step 20 | -- |
20 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 2 |
