For 1990-2009 cars

## Blower Motor High 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 HI.
4. Use an unpowered test lamp in order to backprobe the blower relay connector between terminal 85 and ground. Refer to Probing Electrical Connectors in Wiring Systems.

Does the test lamp light?

--

Go to Step 2

Go to Step 7

2 | Use an unpowered test lamp in order to backprobe the blower relay connector from terminal 87 to ground. Refer to Probing Electrical Connectors in Wiring Systems. Does the test lamp light? | -- | Go to Step 3 | Go to Step 6
3 | Inspect for an open in CKT 1550 between the high speed blower relay connector terminal 86 and splice S108. Did you find an open? | -- | Go to Step 4 | Go to Step 5
4 | Repair the open in CKT 1550. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Step 5 | --
5 |

1. Inspect the high speed blower relay for a poor connection. Refer to Intermittents and Poor Connections .
2. If the connection is OK, replace the blower relay.

Is the repair complete?

--

System OK

--

6 | Repair the open in CKT 442 between the high speed blower relay connector terminal 87 and the right underhood fuse block fuse 3. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | System OK | --
7 | Use an unpowered test lamp to backprobe the HVAC control assembly connector from connector C1 terminal C to ground. Refer to Probing Electrical Connectors in Wiring Systems. Does the test lamp light? | -- | Go to Step 8 | Go to Step 9
8 |

1. Inspect for a poor connection at connector C200 terminal J8. Refer to Intermittents and Poor Connections .
2. If the connection is OK, repair the open or short to ground in CKT 52. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

System OK

--

9 |

1. Inspect for a poor connection at the HVAC control assembly. Refer to Intermittents and Poor Connections .
2. If the connection is OK, replace the HVAC control assembly. Refer to Control Assembly Replacement .

Is the repair complete?

--

System OK

--

## Blower Motor High 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 HI.
4. Use an unpowered test lamp in order to backprobe the blower relay connector between terminal 85 and ground. Refer to Probing Electrical Connectors in Wiring Systems.

Does the test lamp light?

--

Go to Step 2

Go to Step 7

2 | Use an unpowered test lamp in order to backprobe the blower relay connector from terminal 87 to ground. Refer to Probing Electrical Connectors in Wiring Systems. Does the test lamp light? | -- | Go to Step 3 | Go to Step 6
3 | Inspect for an open in CKT 1550 between the blower relay connector terminal 86 and splice S108. Did you find an open? | -- | Go to Step 4 | Go to Step 5
4 | Repair the open in CKT 1550. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Step 5 | --
5 |

1. Inspect the blower relay for a poor connection. Refer to Intermittents and Poor Connections .
2. If the connection is OK, replace the blower relay.

Is the repair complete?

--

System OK

--

6 | Repair the open in CKT 442. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | System OK | --
7 | Use an unpowered test lamp in order to backprobe the HVAC control assembly connector from connector C3 terminal B to ground. Refer to Probing Electrical Connectors in Wiring Systems. Does the test lamp light? | -- | Go to Step 8 | Go to Step 9
8 |

1. Inspect for a poor connection at connector C200 terminal J8. Refer to Intermittents and Poor Connections .
2. If the connection is OK, repair the open or short to ground in CKT 52. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

System OK

--

9 |

1. Inspect for a poor connection at the HVAC control assembly. Refer to Intermittents and Poor Connections .
2. If the connection is OK, replace the HVAC control assembly. Refer to Control Assembly Replacement .

Is the repair complete?

--

System OK

--

## Blower Motor High 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 HI.
4. Use an unpowered test lamp in order to backprobe the blower relay connector between terminal 85 and ground. Refer to Probing Electrical Connectors in Wiring Systems.

Does the test lamp light?

--

Go to Step 2

Go to Step 7

2 | Use a unpowered test lamp in order to backprobe the blower relay connector from terminal 87 to ground. Refer to Probing Electrical Connectors in Wiring Systems. Does the test lamp light? | -- | Go to Step 3 | Go to Step 6
3 | Inspect for an open in CKT 1550 between the blower relay connector terminal 86 and splice S108. Did you find an open? | -- | Go to Step 4 | Go to Step 5
4 | Repair the open in CKT 1550. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Step 5 | --
5 |

1. Inspect the blower relay for a poor connection. Refer to Intermittents and Poor Connections .
2. If the connection is OK, replace the blower relay.

Is the repair complete?

--

System OK

--

6 | Repair the open in CKT 442. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | System OK | --
7 | Use an unpowered test lamp in order to backprobe the HVAC control assembly connector from connector C2 terminal C to ground. Refer to Probing Electrical Connectors in Wiring Systems. Does the test lamp light? | -- | Go to Step 8 | Go to Step 9
8 |

1. Inspect for a poor connection at connector C200 terminal J8. Refer to Intermittents and Poor Connections .
2. If the connection is OK, repair the open or short to ground in CKT 52. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

System OK

--

9 |

1. Inspect for a poor connection at the HVAC control assembly. Refer to Intermittents and Poor Connections .
2. If the connection is OK, replace the HVAC control assembly. Refer to Control Assembly Replacement

Is the repair complete?

--

System OK

--