2003 LEXUS LS430 Factory Repair Manual

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LEXUS LS430 2003  Factory Repair Manual Fig. 3: Electronic Controlled Automatic Transmission System Diagram (1 Of 2) 
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

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LEXUS LS430 2003  Factory Repair Manual Fig. 4: Electronic Controlled Automatic Transmission System Diagram (2 Of 2) 
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

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LEXUS LS430 2003  Factory Repair Manual Fig. 5: Electronic Controlled Automatic Transmission Circuit Diagram 
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

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LEXUS LS430 2003  Factory Repair Manual SYSTEM DESCRIPTION 
1.SYSTEM DESCRIPTION 
a. The ECT (Electronic controlled automatic transmission) is an automatic transmission that 
electronically controls shift timing using the ECM. The ECM detec

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LEXUS LS430 2003  Factory Repair Manual NG: Go to step 19  
OK: Go to next step  
11.Mechanical System Test (See MECHANICAL SYSTEM TESTS
 ) 
NG: Go to step 16  
OK: Go to next step  
12.Hydraulic Test (See HYDRAULIC TEST
 ) 
NG: Go to step

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LEXUS LS430 2003  Factory Repair Manual Fig. 6: Customer Problem Analysis Check Sheet 
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC. 
ROAD TEST 
1.PROBLEM SYMPTOM CONFIRMATION 
a. Based on the result of the customer problem analysis, try to

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LEXUS LS430 2003  Factory Repair Manual a. D position test: 
Shift into the D position and fully depress the accelerator pedal and check the following points. 
1. Check up-shift operation. 
Check that 1 --> 2,2 --> 3,3 --> 4,4 --> 5 and 5 -

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LEXUS LS430 2003  Factory Repair Manual 6. Check the lock-up mechanism. 
Drive in the D position (4th, 5th or 6th gear), at a steady speed (lock-up ON).  
Lightly depress the accelerator pedal and check that the engine speed does not change