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LS400 & SC400

CAUTION: Some tachometers may not be compatible with ignition system. Consult tachometer manufacturer before connecting tachometer to system. DO NOT allow tachometer terminal to become grounded, or damage to ignitor and/or coil may occur.
  1. Connect timing light to No. 6 spark plug wire. Connect tachometer to IG- terminal of engine check connector. Bring engine to normal operating temperature. See Fig 1 or Figure.
  2. Install jumper wire between terminals TE1 and E1 of engine check connector. See Fig 2 or Figure. Ensure idle speed is within specification. See IDLE SPEED SPECIFICATIONS  table under IDLE SPEED & MIXTURE. Ensure base timing is within specification. See IGNITION TIMING  table under ES300. Remove jumper wire from engine check connector.
  3. If ignition timing is not within specifications, check the following: Ensure throttle valve is fully closed. Ensure there is continuity between terminals IDL and E2 of throttle position sensor. Check valve timing.
Fig 1: Installing Tachometer (LS400)
G90B20769Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 2: Installing Timing Jumper Wire (LS400)
G90E20770Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002