GS300 & SC300

Start engine and warm engine to normal operating temperature. Shut engine off. Connect scan tool to data link connector No. 3. See Fig 1. Scan tool is used to read engine RPM.
Connect timing light lead to White wire at ignitor. See Fig 2 and Fig 3 . Ignitor is located on top of driver's side strut tower.
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.
Install Jumper Wire (SST 09843-18020) between terminals TC and E1 on data link connector No. 1. On GS300, data link connector No. 1 is located near driver's side strut tower. See Fig 4. On SC300, data link connector No. 1 is located on end of air intake chamber. See Fig 5.
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 data link connector No. 1. Ensure ECM controlled timing is 6-16 degrees BTDC. Shut engine off. Remove timing light and scan tool.

Fig 1: Connecting Scan Tool To Typical Data Link Connector No. 3 (GS300, GS400, LS400, LX470, SC300 & SC400)
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Fig 2: Connecting Timing Light At Ignitor (GS300)
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Fig 3: Connecting Timing Light At Ignitor (SC300)
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Fig 4: Installing Jumper Wire Between Data Link Connector No. 1 Terminals (GS300)
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Fig 5: Installing Jumper Wire Between Data Link Connector No. 1 Terminals (SC300)
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