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Category 1: Electronic Circuit Matrix Chart

ELECTRONIC CIRCUIT MATRIX

Symptom Suspect Area Action
No up-shift (A particular gear, from 1st to 4th gear, is not up-shifted) ECM INSPECTION, Connectors, Terminal pins, Wiring Harness (Open or Short Circuits)
No up-shift (4th --> 5th)
  1. Transmission control switch circuit
  2. ECM
  1. DTC P0705 TRANSMISSION RANGE SENSOR CIRCUIT MALFUNCTION (PRNDL INPUT)
  2. INSPECTION, Connectors, Terminal pins, Wiring Harness (Open or Short Circuits)
No down-shift (5th --> 4th)
  1. Transmission control switch circuit
  2. ECM
  1. DTC P0705 TRANSMISSION RANGE SENSOR CIRCUIT MALFUNCTION (PRNDL INPUT)
  2. INSPECTION, Connectors, Terminal pins, Wiring Harness (Open or Short Circuits)
No down-shift
(A particular gear, from 1st to 4th gear, is not up-shifted)		 ECM INSPECTION, Connectors, Terminal pins, Wiring Harness (Open or Short Circuits)
No lock-up ECM INSPECTION, Connectors, Terminal pins, Wiring Harness (Open or Short Circuits)
No lock-up off ECM INSPECTION, Connectors, Terminal pins, Wiring Harness (Open or Short Circuits)
Shift point too high or too low
  1. Pattern select switch circuit
  2. ECM
  1. PATTERN SELECT SWITCH CIRCUIT
  2. INSPECTION, Connectors, Terminal pins, Wiring Harness (Open or Short Circuits)
Up-shift to 5th from 4th while shift lever is 4 position
  1. Transmission control switch circuit
  2. ECM
  1. DTC P0705 TRANSMISSION RANGE SENSOR CIRCUIT MALFUNCTION (PRNDL INPUT)
  2. INSPECTION, Connectors, Terminal pins, Wiring Harness (Open or Short Circuits)
Up-shift to 5th from 4th while engine is cold ECM INSPECTION, Connectors, Terminal pins, Wiring Harness (Open or Short Circuits)
No kick-down ECM INSPECTION, Connectors, Terminal pins, Wiring Harness (Open or Short Circuits)
No pattern select
  1. Pattern select switch circuit
  2. ECM
  1. PATTERN SELECT SWITCH CIRCUIT
  2. INSPECTION, Connectors, Terminal pins, Wiring Harness (Open or Short Circuits)
Engine stalls when starting off or stopping ECM INSPECTION, Connectors, Terminal pins, Wiring Harness (Open or Short Circuits)
No kick-down ECM IINSPECTION, Connectors, Terminal pins, Wiring Harness (Open or Short Circuits)
No 2nd start
  1. Pattern select switch circuit
  2. ECM
  1. PATTERN SELECT SWITCH CIRCUIT
  2. INSPECTION, Connectors, Terminal pins, Wiring Harness (Open or Short Circuits)
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