Accessory Drive — Symptom Chart — Accessory Drive - 2.3L EcoBoost (231kW & 314PS) · Reference 4524

2. Small scattered pills. Not considered a concern. No action required.

3. Longer pills up to 50% of the rib height. Possible noise concern. INSTALL a new accessory drive belt if noise is apparent. REFER to: Accessory Drive Belt .

4. Longer pills up to 50% of the rib height. Possible noise concern. INSTALL a new accessory drive belt if noise is apparent. REFER to: Accessory Drive Belt .

5. Heavy deposits in the grooves. Possible noise and stability concern. INSTALL a new accessory drive belt. REFER to: Accessory Drive Belt .

6. Heavy deposits in the grooves. Possible noise and stability concern. INSTALL a new accessory drive belt. REFER to: Accessory Drive Belt .

Incorrect fitment

Accessory drive belt noise can be generated by the accessory drive belt being incorrectly fitted on the pulley as shown in the following illustration. Make sure that all the V grooves on the accessory drive belt contact correctly with the pulley.

Accessory Drive — original illustration 1, reference 4524Original colors & callouts · Select to enlarge

4. If the cause is not visually evident, verify the symptom and refer to the Symptom Chart .

DIAGNOSIS AND TESTING > ACCESSORY DRIVE > SYMPTOM CHART

Symptom	Possible Sources	Action
Accessory drive belt noise	Accessory drive system	Use a stethoscope or other listening device to determine the source of the noise. INSTALL new

Ford_Mustang_all_2015-2017.pdf · source reference 4524

Original technical text and illustrations, formatted as HTML. Follow the engine, transmission, equipment, model and year specified in the source. Import and layout checks do not establish applicability to every 2015–2017 Mustang. About this collection.