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Chapter 1: Electronic Circuit Matrix Chart

WARNING: This page is about a different car, the 2003 Lexus LS 430. However, it is still accessible from the selected car via links, so may be relevant.
PROBLEM SYMPTOMS

Symptom Suspect Area See article
No up-shift
(A particular gear, from 1st to 4th gear, is not up-shifted)		 ECM HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE
No up-shift (4th --> 5th)
  1. Transmission control switch circuit
  2. ECM
 DTC P0705 Transmission Range Sensor Circuit Malfunction (PRNDL Input) 
HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE
No down-shift (5th --> 4th)
  1. Transmission control switch circuit
  2. ECM
 DTC P0705 Transmission Range Sensor Circuit Malfunction (PRNDL Input) 
HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE
No down-shift
(A particular gear, from 1st to 4th gear, is not up-shifted)		 ECM HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE
No lock-up ECM HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE
No lock-up off ECM HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE
Shift point too high or too low
  1. Pattern select switch circuit
  2. ECM
 PATTERN SELECT SWITCH CIRCUIT 
HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE
Up-shift to 5th from 4th while shift lever is 4 position
  1. Transmission control switch circuit
  2. ECM
 DTC P0705 Transmission Range Sensor Circuit Malfunction (PRNDL Input) 
HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE
Up-shift to 5th from 4th while engine is cold ECM HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE
No kick-down ECM HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE
No pattern select
  1. Pattern select switch circuit
  2. ECM
 PATTERN SELECT SWITCH CIRCUIT 
HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE
Engine stalls when starting off or stopping ECM HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE
No kick-down ECM HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE
No 2nd start
  1. Pattern select switch circuit
  2. ECM
 PATTERN SELECT SWITCH CIRCUIT 
HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE
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