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Drive Belt Tension Check

Generator Drive Belt Tension Check
Check the drive belt tension as follows:





Standard value:


Required Special Tools:
MB991502: Scan Tool (MUT-II)
MB991668: Belt Tension Meter Set





1. Connect special tool MB991668 to the scan tool MB991502.

CAUTION: To prevent damage to scan tool MB991502, always turn the ignition switch to "LOCK" (OFF) position before connecting or disconnecting scan tool MB991502.





2. Connect scan tool MB991502 to the data link connector.
3. Turn the ignition switch to the "ON" position and select scan tool MB991502 melt Tension Measurement from the menu screen.
4. Hold the special tool MB991668 (microphone) to the middle of the drive belt between the pulleys (at the place indicated by the arrow), about 10 - 20 mm (0.4 - 0.8 inch) away from the rear surface of the belt and so that it is perpendicular to the belt (within an angle of ±15 degree angle).

CAUTION:
- The temperature of the surface of the belt should be as close as possible to normal temperature.
- Do not let any contaminants such as water or oil get onto the microphone.
- If strong gusts of wind blow against the microphone or it there are any loud sources of noise nearby, the values measured by the microphone or if there are any loud sources of noise nearby, the values measured by the microphone may not correspond to actual values.
- If the microphone is touching the belt while the measurements is being made, the values measured by the microphone may not correspond to actual values.
- Do not take the measurement while the vehicle's engine is running.

5. Gently tap the middle of the belt between the pulleys (the place indicated by the arrow) with your finger as shown in the figure, and check that the vibration frequency of the belt is within the standard value.






Use a belt tension gauge to check that the belt tension is within the standard value.






Apply 98 N (22 lbs.) of force to the middle (arrow) of the drive belt between the pulleys as shown, and check that the amount of deflection is within the standard value.