Workshop Manuals Factory service & repair Vauxhall
Vauxhall Astra J12 · HVAC
12 · Heating & A/C

Blower Motor Malfunction

Make
Vauxhall
Model
Astra J
Section
HVAC Systems - Automatic › Other Information › Blower Motor Malfunction
HVACBlower Motor Malfunction

Blower Motor Malfunction

Diagnostic Instructions

•  Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
•  Review Strategy Based Diagnosis for an overview of the diagnostic approach.
•  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Diagnostic Fault Information



Circuit
Short to Ground
Open/High Resistance
Short to Voltage
Signal Performance

Blower Motor Control Module B+
B0193 06
B0193 06
-
-

Blower Motor B+
1
1
-
-

Blower Motor Control Module Control
B0193 06
B0193 06
B0193 01
-

Blower Motor Control
2
1
1
-

Blower Motor Control Module Ground
-
1
-
-

1. Blower Motor Inoperative

2. Blower Motor Always ON
 

Circuit/System Description

The blower motor control module is an interface between the HVAC control module and the blower motor. The blower motor speed control from the HVAC control module, battery positive and ground circuits enable the blower motor control module to operate. The HVAC control module provides a pulse width modulation (PWM) signal to the blower motor control module in order to command the blower motor speed. The blower motor control module transfers the PWM signal into a corresponding blower motor voltage. The voltage amounts to between 2-13 V and changes linear to the reading of the PWM signal.

Diagnostic Aids

Check the following mechanical fault sources:

•  Air distribution box
•  Air distribution hoses/air distribution ducts

Reference Information


Schematic Reference

HVAC Schematics


Connector End View Reference

Component Connector End Views


Description and Operation

Automatic HVAC Description and Operation


Electrical Information Reference


Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON, press and release the switch for blower speed increase. Verify the scan tool Blower Motor Switch parameter changes between Inactive and Up.
    ⇒  If the parameter does not change

Replace the A26 HVAC Controls.     ⇓  If the parameter changes

2. Press and release the switch for blower speed decrease. Verify the scan tool Blower Motor Switch parameter changes between Inactive and Down.
    ⇒  If the parameter does not change

Replace the A26 HVAC Controls.     ⇓  If the parameter changes

3. All OK.

Circuit/System Testing

1. Ignition OFF, disconnect the X1 harness connector at the K8 Blower Motor Control Module, ignition ON.
2. Verify that a test lamp illuminates between the ground circuit terminal 5 X1 and B+.
    ⇒  If the test lamp does not illuminate

Repair the open/high resistance in the circuit.     ⇓  If the test lamp illuminates

3. Verify that a test lamp illuminates between the B+ circuit terminal 6 X1 and ground.
    ⇒  If the test lamp does not illuminate and the circuit fuse is good

  3.1 Ignition OFF.
  3.2 Test for less than 2 Ω in the B+ circuit end to end.
⇒  If 2 Ω or greater, repair the open/high resistance in the circuit.
⇒  If less than 2 Ω, verify the fuse is not open and there is voltage at the fuse.
    ⇒  If the test lamp does not illuminate and the circuit fuse is open

  3.1 Ignition OFF.
  3.2 Test for infinite resistance between the B+ circuit and ground.
⇒  If less than infinite resistance, repair the short to ground on the circuit.
⇓  If infinite resistance
  3.3 Disconnect the X2 harness connector at the K8 Blower Motor Control Module.
  3.4 Test for infinite resistance between the B+ circuit terminal 1 X2 and ground.
⇒  If less than infinite resistance, replace the M8 Blower Motor.
⇓  If infinite resistance
  3.5 Install a jumper wire between the ground circuit terminal 2 X2 and ground.
  3.6 Install a 40 A fused jumper wire between the B+ circuit terminal 1 X2 and B+ and verify the fuse is good.
⇒  If the fuse is open, replace the M8 Blower Motor.
⇒  If the fuse is good, replace the K8 Blower Motor Control Module.
    ⇓  If the test lamp illuminates

4. Ignition OFF, disconnect the X2 harness connector and connect the X1 harness connector at the K8 Blower Motor Control Module.
5. Connect a test lamp between the K8 Blower Motor Control Module's B+ circuit terminal 1 X2 and the control circuit terminal 2 X2.
6. Ignition ON, turn the blower motor OFF.
7. Verify the test lamp does not illuminate.
    ⇒  If the test lamp illuminates

  7.1 Ignition OFF, replace the K8 Blower Motor Control Module, ignition ON.
  7.2 Verify the test lamp does not illuminate.
⇒  If the test lamp illuminates, replace the K33 HVAC Control Module.
⇒  If the test lamp does not illuminate, all OK.
    ⇓  If the test lamp does not illuminate

8. Turn the blower motor stepwise from low speed to high speed. The test lamp intensity should increase.
    ⇒  If the test lamp does not illuminate or the intensity does not vary

  8.1 Ignition OFF, replace the K8 Blower Motor Control Module, ignition ON.
  8.2 Turn the blower motor stepwise from low speed to high speed. The test lamp intensity should increase.
⇒  If the test lamp does not illuminate or the intensity does not vary, replace the K33 HVAC Control Module.
⇒  If the test lamp intensity varies, all OK.
    ⇓  If the test lamp intensity varies

9. Replace the M8 Blower Motor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

•  Control Module References for HVAC control module replacement, programming and setup

Parts & tools for this job For Vauxhall Astra

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