| 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 |
|
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: HVAC Schematics 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 at one speed only? | Go to Step 3 | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems |
3 | Test the affected blower speed circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. 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 in Wiring Systems. Did the blower motor resistor test OK? | Go to Step 6 | Go to Step 5 |
5 | Replace the blower motor resistor. Refer to Blower Motor Resistor Replacement . Did you complete the replacement? | Go to Step 8 | -- |
6 | 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 in Wiring Systems. Did you find and correct the condition? | Go to Step 8 | Go to Step 7 |
7 | Replace the blower switch. Refer to Blower Switch Replacement . 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 |
