Troubleshooting the air-conditioning system in an Oldsmobile Bravada before temperatures increase in the summer is a task that doesn't require a high level of expertise. Problems routinely encountered can be simple to diagnose. Common problems can arise with a leaky hose or magnetic clutch. Run through a few troubleshooting steps before taking your vehicle in for a service.
Turn on the fan and air conditioner to test whether any controls are damaged. If the controls are loose or difficult to move, replace them. If the fan does not engage, a fuse might have blown or the fan could be faulty.
To check for blown fuses, find the fuse box. Its location varied in models produced from 1991 to 2004, but it typically is found beneath the steering column/dashboard on the right. There should be a small panel fastened with a screw. Unscrew the panel and read the instructions on the fuse box's cover to identify which fuse corresponds to the air conditioner. If the fuse is damaged, replace it.
Test that the valve control is operating by checking the two heater hoses under the hood with the engine running. The heater hoses protrude from the firewall. The hoses are similar to the thickness of a garden hose. The firewall divides the engine compartment and passenger compartment. Place your hand on the two heater hoses. They should be warm. However, one should be noticeably cooler than the other. If not, it might mean that the valve control must be replaced. Have a qualified mechanic investigate further.
With the engine on, also turn up the air conditioner to its coldest setting. Look under the hood to see whether the magnetic clutch connected to the air conditioner's compressor engages. If you do not see or hear the clutch begin to spin, the system might be low on refrigerant. Have a mechanic refill the system. An extremely noisy compressor also might mean that it is close to failing.
Check all air-conditioning system hoses for leaks. If you notice a green, oily residue on them, they might be damaged and need to be replaced.
Use an AC compression test gauge with the engine off to check the system for adequate pressure. The test gauge has red and blue hoses attached to red and blue monitors to calculate the pressure. Remove the black caps from the service ports on the vehicle's air-conditioning unit. Screw the blue hose to the low-side service port and the red hose to the high-side port. Check the pressure readings on the monitors. A normal pressure reading should be between 50 psi and 80 psi. If not, this might mean there is a leak. Have a qualified mechanic investigate further.
