For 1990-2009 cars

## Blower Motor Low Speed Inoperative Buick

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 |

1. Turn the ignition switch to the RUN position.
2. Set the HVAC control to RECIRC.
3. Set the blower speed to LO.
4. Use an unpowered test lamp in order to backprobe the blower relay connector between terminal 87A and ground. Refer to Probing Electrical Connectors in Wiring Systems.

Does the test lamp light?

--

Go to Step 2

Go to Step 3

2 |

1. Inspect the blower resistor assembly connector for a poor connection. Refer to Intermittents and Poor Connections .
2. If the connection is OK, replace the blower resistor assembly. Refer to Blower Motor Resistor Replacement .

Is the repair complete?

--

System OK

--

3 | Inspect for an open in CKT 188 between splice S103 and the blower resistor assembly. Did you find an open? | -- | Go to Step 4 | Go to Step 5
4 | Repair the open in CKT 188. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Step 5 | --
5 | Inspect for a short to ground in CKT 188 between splice S103 and the blower resistor assembly. Did you find a short to ground? | -- | Go to Step 6 | Go to Step 7
6 | Repair the open in CKT 188. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Step 7 | --
7 | Replace the HVAC control assembly. Refer to Control Assembly Replacement . Is the repair complete? | -- | System OK | --

## Blower Motor Low Speed Inoperative Oldsmobile

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 |

1. Turn the ignition switch to the RUN position.
2. Set the HVAC control to MAX-A/C.
3. Set the blower speed to LOW.
4. Use an unpowered test lamp in order to backprobe the relay connector between terminal 87A and ground. Refer to Probing Electrical Connectors in Wiring Systems.

Does the test lamp light?

--

Go to Step 2

Go to Step 3

2 |

1. Inspect the blower resistor assembly connector for a poor connection. Refer to Intermittents and Poor Connections .
2. If the connection is OK, replace the blower resistor assembly. Refer to Blower Motor Resistor Replacement .

Is the repair complete?

--

System OK

--

3 | Inspect for an open in CKT 60. Did you find an open? | -- | Go to Step 4 | Go to Step 5
4 | Repair the open in CKT 60. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Step 5 | --
5 |

1. Inspect the following components for a poor connection:

• | Connector C200 terminal E2. Refer to Intermittents and Poor Connections .

• | The heater-A/C control assembly. Refer to Intermittents and Poor Connections .

2. If the connections are OK, replace the HVAC control assembly. Refer to Control Assembly Replacement .

Is the repair complete?

--

System OK

--

## Blower Motor Low Speed Inoperative Pontiac

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 |

1. Turn the ignition switch to the RUN position.
2. Set the HVAC control to MAX-A/C.
3. Set the blower speed to low.
4. Use an unpowered test lamp in order to backprobe the relay connector between terminal 87A and ground. Refer to Probing Electrical Connectors in Wiring Systems.

Does the test lamp light?

--

Go to Step 2

Go to Step 3

2 |

1. Inspect the blower resistor assembly connector for a poor connection. Refer to Intermittents and Poor Connections .
2. If the connection is OK, replace the blower resistor assembly. Refer to Blower Motor Resistor Replacement .

Is the repair complete?

--

System OK

--

3 | Inspect for an open in CKT 60. Did you find an open? | -- | Go to Step 4 | Go to Step 5
4 | Repair the open in CKT 60. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Step 5 | --
5 |

1. Inspect the following components for a poor connection:

• | Connector C200 terminal E2. Refer to Intermittents and Poor Connections .

• | The HVAC control assembly. Refer to Intermittents and Poor Connections .

2. If the connections are OK, replace the HVAC control assembly. Refer to Control Assembly Replacement .

Is the repair complete?

--

System OK

--