1. Fuses and Relays:
* Locate the fuse box: Your owner's manual will show you the location(s) of the fuse boxes (there's usually one under the hood and one inside the car, often under the dash).
* Check the blower motor fuse: Look for a fuse specifically labeled "blower motor," "HVAC," or something similar. Visually inspect it for a blown filament (a broken wire inside). Replace it with a fuse of the *same amperage* rating.
* Check the blower motor relay: The relay acts as a switch controlled by the controls. It's often located in the same fuse box. Try swapping it with a relay of the *same type* from a different, non-essential circuit (like the wipers – but only if you're comfortable with this and know how to identify relays). If swapping fixes the problem, the relay is bad.
2. Blower Motor Resistor:
* Location: The blower motor resistor is a common point of failure. It controls the fan speeds. Its location varies slightly by year, but it's often found behind the glove compartment or under the dashboard. You may need to remove some panels to access it.
* Testing: You can try testing the resistor with a multimeter (if you have one), but often the best test is just replacing it. It's relatively inexpensive. If you find it, and it's damaged or looks burnt, replacing it is likely the solution.
3. Blower Motor:
* Access: Accessing the blower motor requires some disassembly, usually involving removing parts of the dashboard. This is more involved than the previous steps.
* Testing: You can test the motor itself with a multimeter to see if it's receiving power and if it's functioning. However, this often requires disconnecting wires and might be difficult to reach.
* Replacement: If the motor is faulty, it'll need to be replaced.
4. Wiring and Connections:
* Inspect Wiring: Carefully inspect all wiring leading to the blower motor, the resistor, and the relay. Look for any damaged, frayed, or loose wires. Corrosion can also be a problem, especially in older vehicles.
* Check Connections: Make sure all connectors are securely plugged in. Sometimes a loose connection can cause intermittent or complete fan failure.
5. Blower Motor Switch (Control):
* Testing: This is usually the least likely culprit when *neither* heat nor AC fan works, but it's possible. It might require removing the dash panel and testing with a multimeter to ensure it's sending the appropriate signals.
Before you start:
* Consult a repair manual: A repair manual specific to your 1999 Oldsmobile Intrigue will provide diagrams and detailed instructions for accessing components and performing tests. This is highly recommended.
* Safety First: Disconnect the negative battery terminal before working on any electrical components.
If you're not comfortable performing these checks yourself, it's best to take your car to a qualified mechanic. The problem could be something relatively simple (like a fuse) or more complex (requiring significant disassembly). Starting with the easiest checks (fuses and relays) is the most cost-effective approach.
