For 1990-2009 cars

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

1. Turn the ignition to the OFF position.
2. Disconnect the HVAC programmer connector.
3. Connect a fused jumper across the blower motor connector terminal A and terminal B.

Refer to Using Fused Jumper Wires in Wiring Systems.

4. For Oldsmobile and Buick, measure the resistance between HVAC programmer connector terminal F2 and ground.

Refer to Testing for Continuity in Wiring Systems.

5. For Pontiac, measure the resistance between HVAC programmer connector terminal D2 and ground.

Refer to Testing for Continuity in Wiring Systems.

Is the resistance less than the specified value?

5 ohms

Go to Step 2

Go to Step 5

2 | Inspect CKT 754 (GRY/BLK) for a short to voltage. Did you find short to voltage? | -- | Go to Step 3 | Go to Step 4
3 | Repair CKT 754 (GRY/BLK) short to voltage. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | System OK | --
4 |

1. For Oldsmobile and Buick, inspect the HVAC programmer connector terminal F2 for proper terminal contact.
2. For Oldsmobile and Buick, inspect the HVAC programmer connector terminal F2 for proper terminal contact.

Refer to Intermittents and Poor Connections Diagnosis in Wiring Systems.

3. If the terminal contact is OK, replace the heater and A/C programmer. Refer Programmer Replacement .

Is the repair complete?

--

System OK

--

5 | Inspect CKT 761 and CKT 65 for an open. Did you find an open? | -- | Go to Step 6 | Go to Step 7
6 | Repair the open in CKT 761 and CKT 65. Is the repair complete? | -- | Go to Step 7 | System OK
7 | Inspect CKT 761 for a short to ground. Did you find a short to ground? | -- | Go to Step 8 | System OK
8 | Repair the short in CKT 761. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | System OK | --