There are separate fuses for the left and right horns on your 2013 Jeep Grand Cherokee. If a horn doesn't work, check the fuses in the Totally Integrated Power Module on the passenger side of the engine compartment behind the coolant reservoir. Both are red, 10A fuses. The right horn fuse is in slot No. M22; the left is in slot No. M23.
The plastic rivets in the fender flares on your Grand Cherokee are single-use fasteners, and you'll have to remove them to replace the horns, so buy new rivets first.
Wrap masking tape around the tip of a flat-head screwdriver. Remove the plastic rivets on the fender flares over the wheel openings. Pry with the protected tip to avoid damaging painted surfaces. Release the clips that secure the flares to the front fascia and disengage the forward ends of the flares. Remove the three screws that hold each wheel well liner to the front fascia.
Turn the 1/4-turn fasteners counterclockwise to separate the lower wheel well liner from the front fascia. Remove the four screws across the bottom of the front fascia. Disengage the clips at the wheel well openings and the radiator grille assembly. Disconnect the fog lamp wiring connectors and remove the front fascia.
Remove the two screws -- one on the lower corner on each side -- that hold the radiator grille to the Grand Cherokee. Pull up on the grille to disengage the four upper retaining tabs from the radiator core support, then remove the grille assembly.
Disconnect the connectors from the horns. Remove the horn bracket screws -- one from each horn -- that holds the bracket to the upper radiator crossmember. Remove each horn and mounting bracket as a unit.
Position the new horns. Install the bracket screws and tighten them to 53 inch-pounds. Reconnect the horn connectors. Position the grille and press across the top to engage the four retaining tabs. Install and tighten the two screws at the lower corners of the grille.
Connect the fog lamp connectors to the front fascia. Engage the clips at the radiator grille and at the wheel well openings. Install the four screws across the bottom of the fascia. Install and tighten the screws that hold the wheel well liners to the front fascia.
Press the fender flares into place and engage the retaining clips. Install the plastic rivets in the flares. Turn the 1/4-turn fasteners clockwise to secure the lower wheel well liner to the front fascia.
