GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Isuzu 🢒 2001 🢒 S/T Isuzu - 4WD 🢒 HVAC 🢒 HVAC Systems - Manual 🢒 Air Delivery Improper

Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

  1. This step tests for a blower motor that does not operate regardless of the desired blower motor speed.

    2.

  2. This step tests for a blower motor that operates, yet does not accurately respond to the desired blower motor speed.

Step

Action

Value(s)

Yes

No

Schematic Reference: HVAC Schematics

DEFINITION: Air does not flow correctly from the air distribution outlets.

1

Did you review the HVAC operation and perform the necessary inspections?

--

Go to Step 2

Go to Diagnostic System Check - HVAC Systems - Manual

2
  1. Turn ON the ignition, with the engine OFF.
  2. Place the blower control in the OFF position.

Is the blower motor OFF?

--

Go to Step 3

Go to Blower Motor Always On

3

Place the blower control in each speed position.

Does the blower motor operate at all?

--

Go to Step 4

Go to Blower Motor Inoperative

4

Does the blower motor operate correctly for each speed position?

--

Go to Step 5

Go to Blower Motor Malfunction

5

  1. Start the engine
  2. Place the blower control in the maximum speed position.
  3. Place the mode control in each mode position.

Does the air flow from the correct air distribution outlet(s) for each mode selected?

--

Go to Testing for Intermittent Conditions and Poor Connections

Go to Vacuum Control System Diagnostic