How to Replace the Battery in a 2003 Pontiac Montanaby Christian Killian
The battery in the 2003 Pontiac Montana is located in the engine compartment on the passenger’s side just behind the headlight assembly. Changing the battery can be a little challenging because the Pontiac saw fit to bury it below several other parts in the van. The under-hood fuse box sits directly above the battery and a cross brace runs over the top of it as well. Dealing with both items is not complicated but does add time to the process.
Locate and remove the bolt holding the under hood fuse box in place using a socket and ratchet. It is located on the radiator support directly behind the passenger’s side headlight assembly. Lift the fuse box and set it of the way.
Locate the black tubular brace that runs from the passenger’s side firewall to the passenger’s side of the radiator support. Remove the two bolts on the radiator support end of the bar with a socket and ratchet then swing it back toward the engine.
Locate the battery on the passenger’s side of the engine compartment and remove both battery cables with a wrench, starting with the negative cable first. Lay the wires aside.
Remove the retaining bolt from the plastic clamp near the base of the battery. You will need an extension, socket and ratchet to remove this bolt. Lift the plastic clamp out of the engine compartment the lift and remove the battery from the van.
Position a new battery on the tray in the engine compartment. Make sure you are using the same type and size of battery as the original or it may not fit in the space provided. Place the plastic clamp in place, insert the retaining bolt and tighten it with a socket, ratchet and extension.
Connect the positive battery cable to the battery terminal and tighten the retaining bolt with a wrench. Connect the negative battery cable to the negative battery terminal and tighten the retaining bolt with a wrench as well.
Pull the black, tubular brace back into position and install the two bolts that secure it to the radiator support. Tighten the two bolts with a socket and ratchet. Position the under hood fuse box over the battery and inset the mounting bolt that holds it to the radiator support. Tighten the bolt with a socket and ratchet.