| Table 1: | Reference Table |
Symptom | Causes | ||||||
|---|---|---|---|---|---|---|---|
Blower motor inoperative in Low speed only |
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Blower motor inoperative in High speed only |
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Blower motor operates at High speed only |
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Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: HVAC Schematics Connector End View Reference: Component Connector End Views DEFINITION: Blower motor inoperative in Medium 1 or Medium 2. | |||
1 | Did you review the Air Delivery Description and Operation and the Air Temperature Description and Operation perform the necessary inspections? | Go to Step 2 | |
2 | Operate the blower motor at each speed. Is the blower motor inoperative in one speed only? | Go to Step 3 | Go to Testing for Intermittent Conditions and Poor Connections |
3 | Test the blower motor speed circuit for an open in the affected speed. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | Go to Step 8 | Go to Step 4 |
4 | Test the blower motor resistor for an open in the affected speed. Refer to Circuit Testing and Wiring Repairs . Did the blower motor resistor test OK? | Go to Step 5 | Go to Step 6 |
5 | Inspect for a poor connection at the harness connector of the blower switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | Go to Step 8 | Go to Step 7 |
6 | Replace the blower motor resistor. Refer to Blower Motor Resistor Replacement . Did you complete the replacement? | Go to Step 8 | -- |
7 | Replace the blower switch. Did you complete the replacement? | Go to Step 8 | -- |
8 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 3 |
