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GS300 & Is300

  1. Start and warm engine up to normal operating temperature. Shut engine off. Connect scan tool to DLC3. See Fig 1. Use scan tool to read engine RPM. Using a timing light that can detect primary ignition signal, connect inductive lead to appropriate wire at ignitor. See Fig 2. Ignitor is located on top of driver's side strut tower.
  2. Apply parking brake. Place transmission in Neutral. Start engine and maintain engine at 2500 RPM for 90 seconds and allow engine to idle. Ensure idle speed is 650-750 RPM. On GS300, install Jumper Wire (SST 09843-18020) between terminals TC and E1 on DLC1 located near driver's side strut tower. See Fig 3. On IS300, install Jumper Wire (SST 09843-18020) between terminals TC and CG on DLC3 located under right side of instrument panel. See Fig 4.
  3. On all models, timing marks are located on timing belt cover, near crankshaft pulley. Ensure base timing is 8-12 degrees BTDC at idle with transmission in Neutral, and with A/C and all accessories off. Remove jumper wire from DLC1. Ensure ECM controlled timing is 6-16 degrees BTDC. Shut engine off. Remove timing light and scan tool.
Fig 1: Connecting Scan Tool To DLC3 (Typical)
G99F50414Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 2: Connecting Timing Light At Ignitor (GS300 & IS300)
G99I50417Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 3: Installing Jumper Wire Between DLC1 Terminals (GS300)
G99J50418Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 4: Installing Jumper Wire Between DLC3 Terminals TC & CG (IS300)
G00131783Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002