Owners of other Toyota, Lexus or Scion vehicles such as the Yaris, Matrix, Prius, Camry, RAV4, Sienna, Tacoma, Tundra, FJ Cruiser, Venza, Highlander, Avalon, Sequoia, Land Cruiser, IS 250, ES 350, GS 350, tC, xB, xD, iQ and FR-S may also find these DIY instructions to be helpful.

A few compatible replacement belts with their part numbers are as follows: Bando 6PK1220 or Bando 6PK1230, Dayco 5060485, Toyota 90916-02679 (Japan Built), Toyota # 90916-A2016 (North America Built).

The tools needed to complete this procedure include a 12mm socket, a 14mm socket and a 3/8" drive ratchet.

Set the engine cover aside in  a safe place.

If the car has been driven recently, I'd recommend letting the engine cool off for at least an hour or two.

The serpentine accessory belt is located on the left side of the engine.

To release the old belt, you'll need to loosen three bolts.

One bolt is located at the bottom of the alternator.

The second bolt is the tensioner bracket set bolt which is mounted with the bolt head facing toward the left side of the car.

The 3rd and final bolt is the long bolt that tensions the belt by slowly rotating the alternator forwards towards the front of the car.

Loosen the bolt at the bottom of the alternator by turning it counterclockwise with a 14mm socket and a 3/8" drive ratchet.

The top alternator bolt / tensioner bracket set bolt is mounted with the bolt head facing towards the left side of the vehicle.

Continue loosening the long bolt until you can rotate the alternator backwards towards the rear of the car.

A good rule of thumb to remember is that the ribbed side of the belt goes around ribbed pulleys and the smooth side of the belt goes against smooth pulleys.

Inspect the old belt. If the old belt doesn't have any major cracks, chunks missing or fraying, you may want to save it for future use.

2009-2013 Toyota Corolla 2ZR-FE 1.8L I4 Serpentine Accessory Belt Routing Diagram

Start by wrapping the ribbed side of the belt around the large crankshaft pulley.

Then wrap the ribbed side of the belt around the A/C (air conditioning) compress pulley.

Route the smooth side of the new belt against the back side of the water pump pulley.

Firmly pull the alternator forward until it rotates towards the front of the car and places some tension on the new belt.

Double check that the new belt is routed properly before moving on to the next steps.

Tighten the long bolt in the clockwise direction to tension the new belt.

The correct tension level is when the new belt can only be twisted to about 90 degrees.

If the belt can be twisted past 90 degrees, the tensioner bolt needs to be tightened a few more turns.

If the belt can not be twisted to 90 degrees, it might be too tight.

Once you believe that the new belt has the correct amount of tension, you can tighten the 14mm bolt at the bottom of the alternator.

Then tighten the top 12mm alternator bolt in the clockwise direction until it is snug.

If the belt starts screeching immediately and the sound is constant, turn off the engine immediately. This sound indicates that the new belt might be too tight. So instead of the belt spinning, the crankshaft pulley is just rubbing against it in place.

If the new belt repeatedly makes a "chirp, chirp, chirp" sound that doesn't stop, it might be too loose. The belt might also make a quick screech when the engine starts and then it becomes quiet.

To fix a loose belt, slightly loosen the bottom 14mm alternator bolt, the top 12mm alternator bolt. Then tighten the long tensioner bolt in the clockwise direction a few more turns. Check the tension again by trying to twist the longest stretch of the belt in between the alternator and the crankshaft. If the belt can only be turned to about 90 degrees perpendicular to the rest of the belt, that should be the correct tension.

Once the engine is quiet and seems to be running smoothly, you can replace the plastic engine cover.

Line up the rubber friction fasteners on the bottom of the plastic engine cover with the metal mounting pegs on the top of the engine.

Push the engine cover down in to place.

Be sure to record the serpentine accessory belt change in your car's service records.

For more, check out my other 2014-2018 Toyota Corolla DIY Repair & Maintenance Guides.