It depends on the model radio you have, you can Google 1999 owners manuals for your truck and download a free pdf. But 97-2000 had numerous probs w/ radio.
For most models you hold down the clock button or RDS button for a couple seconds then use the seek button till you get to hours the push the button again till you get to minutes.
Alot easier to go here 1999 Mercury Mountaineer owners manual pdf
Mercury Mountaineer was created in 1997.
According to the ( 1999 ) Mercury Mountaineer Owner Guide : ( the length is 188.5 inches )
There are two head gaskets in the V 8 1999 mercury mountaineer
looking for a diagram for 1999 Mercury Mountaineer. Need to take the fuse out for the seatbelt alarm, it will not shut off.
The 1999 Mercury Mountaineer owners manual shows : unleaded fuel only - 87 octane as the recommended fuel
The sub woofer size on a 1999 Mercury Mountaineer is 5 inches by 7 inches. Speakers are located in the front and the rear of the vehicle.
To replace the battery cables on a 1999 Mercury Mountaineer, loosen the connectors at the terminals. After this, remove the other end of the cables and install new ones.
On a 1999 Mercury Mountaineer : The ELECTRIC fuel pump is INSIDE the fuel tank . It is installed through an access hole on the top of the fuel tank
take it off
On a 1999 Mercury Mountaineer , 4.0 liter V6 engine : firewall 3 - 6 2 - 5 1 - 4 front of vehicle
You can check on eBay.
Probably the Mercury Mountaineer.