Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
A constant air rush noise is typical of high speed blower operation. Some systems and modes may be worse than others. If possible inspect another similar vehicle (same model) in order to determine whether the noise is typical of the system as designed or excessive. | ||||
1 | Inspect the blower electrical connections and grounds. Refer to HVAC Blower Control Schematics . Is the repair complete? | -- | -- | |
2 |
Is the blower making a constant whine, tick/click, flutter or scraping noise, but it lessens with a lower blower speed? | -- | ||
3 | Is the blower making a squeal/screech noise at start-up only and/or sometimes intermittent? | -- | ||
4 | Inspect for blower motor and fan vibration at each blower speed by feeling the blower case. Is the vibration excessive? | -- | ||
5 |
Was foreign material found? | -- | ||
6 |
Was any wear found? | -- | ||
7 |
Is the excessive blower noise in VENT mode only? | -- | ||
8 | Is the excessive blower noise in the HEAT and/or DEFROST modes only? | -- | ||
9 | Is excessive blower noise in all modes but not all temperature positions? | -- | ||
10 | Remove the foreign material from the blower assembly. Repair as necessary. Is the repair complete? | -- | -- | |
11 | Repair blower fan and/or blower case as necessary. Is the repair complete? | -- | -- | |
12 | Replace the blower motor and fan. Refer to Blower Motor and Fan Replacement . Is the repair complete? | -- | -- | |
13 |
Is the repair complete? | -- | -- | |
14 |
Is the repair complete? | -- | -- | |
15 | Inspect the temperature door seals and repair as necessary. Is the repair complete? | -- | -- | |
16 | Inspect the heater system for obstruction or foreign material between the blower fan and the temperature door. Repair as necessary. Is the repair complete? | -- | -- | |
17 | Perform the functional test. Refer to Function Test . Is the repair complete? | -- | System OK | -- |
