K 1500 Suburban 4WD V8-393 6.5L DSL Turbo VIN S (1996)
Blower Motor: Testing and Inspection
Blower Noise Diagnosis
A constant air rush noise is typical of high-speed blower operation. Some systems and modes may be noisier than others. If possible, check another
similar vehicle to determine whether the noise is typical or excessive.
Sit in the vehicle with the doors and windows closed. With the engine running, run the blower on "HIGH"speed with the temperature set for maximum
cooling. Cycle through the blower speeds, modes, and temperature settings to find where the noise does not occur. Try to define the types of noise.
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Noise is constant, but decreases with blower speed reduction. Typical noises are a whine, tick/click, flutter, or scrape.
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Noise is only at start-up or intermittent. This noise may occur at cold ambients and low blower speeds. Typical noise is a squeal/screech. Noise
is constant at high blower speeds in certain modes, but can be eliminated at lower blower speeds in other modes. Typical noises are a flutter or
rumble.
If the noise persists, remove the blower assembly and check for obstructions or foreign material causing noise and remove. If no obstructions are
found and the noise is still heard, replace the blower assembly.
