First introduced by Subaru for the 2006 model year, the Tribeca is the larger of the two SUVs manufactured by the Japanese automaker. Subaru offers a troubleshooting guide for diagnosing vehicle problems as part of its "Subaru Technical Information System" program; this program is subscription based, and charges a minimum of $34.95 (as of March 2011) for access. Instead, owner's can use their vehicle's user's guide as a starting point for troubleshooting issues with their Tribeca.
Check your Tribeca's battery for corrosion and loose cable connections. Issues with your battery could be the cause of electrical problems in your vehicle, everything from a radio on the fritz to a car that won't start. Pop the hood of your Tribeca to see if there is any corrosion on the battery. If you see this chalky, yellowish-white substance, remove it by placing a mixture of half baking soda and half water on the terminals. Allow the paste to bubble before removing it with water. Dry with a microfiber cloth. If that doesn't solve the battery problems, examine the cables attached to your battery; if any cables are loose, try securing them back into place.
Use a tire pressure gauge to check the air pressure in your Tribeca's tires. An electronic sensor in the Tribeca will display a low-pressure warning on the dashboard when the pounds per square inch (psi) are under 27; however, it will not tell you how under-inflated your tires are. Under-inflated tires can cause your vehicle to get substandard gas mileage. Place the gauge on your wheel and release a small amount of air from the tire to get a reading. If the pressure is low, use an air compressor to add air until your tires reach the recommended pounds per square inch -- 33 psi for the front tires and 32 psi for the rear tires.
Check the condition of your vehicle's brake pads if your Tribeca experiences problems braking. Remove the wheel from your vehicle, loosen the caliper mounting bolts and remove the caliper mounting unit to expose the brake pads. The Tribeca uses disc brakes, which are protected until the vehicle's initial warranty; premature wear of the brake pads can be replaced at no cost by your Subaru repair shop. If your brake pads are in good condition, the issue might be with the Tribeca's Traction Control System, which applies the brakes automatically when it detects a loss of traction anywhere in the braking system. This problem should be handled only by a licensed repair shop.
Turn off the "Check Engine" light on your Tribeca by checking two parts of the vehicle. Subaru reports that a loose or missing fuel filler cap can cause this light to turn on. Turn off your vehicle, and retighten this gas cap until you hear it click. Turn the vehicle back on to see if the "Check Engine" light is now off. If not, electrically-powered accessories installed in your Tribeca may be to blame. See if removing these add-ons (like a radar detector or remote start system) can turn off the "Check Engine" light.
Examine the belts and hoses under your Tribeca's hood. With the vehicle running, look for bulges or leaks in the hoses connected to your engine. Then turn the vehicle off, and examine any visible belts for cracks or weak spots. These issues could cause your engine to run poorly; contact your local Subaru service shop to schedule a repair.
Check the level of five key fluids on your Tribeca: engine oil, coolant, automatic transmission fluid, manual transmission oil and brake fluid (your Subaru will have either the automatic transmission fluid or the manual transmission oil, not both). Check engine oil and coolant every few weeks by removing the dip sticks on each compartment and looking to see that the fluid level is well above the "low" mark. If not, add enough fluid until it reaches the "full" level. The coolant that comes standard with the Tribeca is known as "Super Coolant," and should not need to be changed or added to for several years after purchase. Automatic transmission fluid (or manual transmission oil) and brake fluid should be checked monthly when the vehicle is warmed up and idling in park. Use the same method described above. Manual transmission oil can be checked using the dip stick while the car is parked and the engine cold. The Tribeca has a history of transmission problems, which can lead to problems shifting. Brake fluid can be checked through a see-through window on the side of the brake fluid compartment; if the fluid is at or below the "MIN" mark, open the compartment and add enough fluid until it reaches the "MAX" mark.
Replace burned-out headlight bulbs. The Tribeca features daytime running lights standard; many Tribeca drivers report headlights burning out early on Subaru enthusiast forums. Pop the hood on your Tribeca, and loosen the screws surrounding the headlight compartment; these compartments are located at the extreme front corners under the hood. Remove the old bulb, and replace with a new one; halogen or LED lights can be used.
