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LS400 & SC400

  1. Ensure engine is at normal operating temperature. Connect timing light magnetic pick-up to spark plug wire for cylinder No. 6. Connect tachometer test lead to terminal IG- of DLC. See Fig 1. Connect jumper wire between terminals TE1 and E1 of DLC.
  2. Ensure idle speed is within specification. See IDLE SPEED SPECIFICATIONS table under IDLE SPEED & MIXTURE. Check base timing. Ensure base timing is within specification. See IGNITION TIMING table. If base timing is not within specification, ensure throttle valve is fully closed, continuity exists between terminals IDL and E2 of throttle position sensor, and valve timing is okay. See Figure. Procedure is complete.
IGNITION TIMING

Application Base Timing (1) (2) Controlled Timing
ES300 10 @ 650-750 10-20 @ 650-750
GS300 10 @ 650-750 8-12 @ 650-750
LS400 8-12 @ 600-700 (3)
SC300
Auto. Trans. 10 @ 600-700 9-11 @ 600-700
Man. Trans. 10 @ 650-750 9-11 @ 650-750
SC400 8-12 @ 650-750 (3)
(1) Jumper wire connected between terminals TE1 and E1 of DLC. See Fig 1
(2) Jumper wire disconnected from DLC.
(3) Information is not available from manufacturer.
Fig 1: Identifying Data Link Connector (DLC) Terminals
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