Tachometer Check

1. Attach an external high quality engine tachometer to the engine speed detection connector on the harness side (such as with a paper clip).
   NOTE: For tachometer check, use an external high quality inductive engine tachometer.
2. Compare the readings of the vehicle engine tachometer and the external engine tachometer at every engine speed, and check if the variations are within the standard values.

Standard values: 

• 700 r/min: +/-100 r/min 
• 3,000 r/min: +/-150 r/min 
• 5,000 r/min: +/-250 r/min 
• 6,000 r/min: +/-300 r/min 
  Fig 1: Attaching An External High Quality Engine Tachometer To The Engine Speed Detection Connector

  Courtesy of DAIMLERCHRYSLER CORPORATION