To control the idle speed the engine control computer

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To control the idle speed, the engine control computer controls the intake air passage of the ISC valve and sends a signal to allow the idle speed to be adjusted towards the target idling speed. DTC P0505/71 ISC VALVE SYSTEM DTC No. DTC Detection Condition 1.Diagnosis Condition 2.Malfunction Condition 3.Malfunction Time 4.Other Suspected Area P0505/33 1. While engine is idling 2. Short or open in ISCV circuit 3. 3 seconds or more 4. 1 trip ISCV Wire harness or connector Engine control computer Throttle Valve Surge Tank Intake Air Signal Engine ECU ISC Valve To Cylinder A050586
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ES–84 ENGINE CONTROL - EFI SYSTEM (3SZ-VE, K3-VE) ES CIRCUIT DIAGRAM INSPECTION PROCEDURE HINT: Read the freeze frame data using the DS-II.Freeze frame data records aspects of the engine's condition when malfunctions occur. This information is helpful when troubleshooting. (a) Following the prompts on the DS-II screen , select ACTIVE TEST. (b) Check that the engine speed changes when the ISC duty ratio is changed. Standard: The engine speed increases or decreases in response to changes in the ISC duty ratio. OK NG 1 PERFORM DS-II ACTIVE TEST (ISC DUTY RATIO) ISCV 1 2 3 ISC To EFI Relay Engine Control Computer 65 A133591J01 CHECK FOR INTERMITTENT PROBLEMS
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ENGINE CONTROL - EFI SYSTEM (3SZ-VE, K3-VE) ES–85 ES (a) Disconnect the ISCV connector. (b) Turn the ignition switch to the ON position. (c) Using a tester, measure the voltage of the ISCV vehicle side connecter terminals. Standard NG OK (a) Disconnect the engine control computer connector A and ISCV connector. (b) Using a tester, check whether there is continuity or a short between the engine control computer and the ISCV.(For terminal layout, see page ES - 16.) Standard NG OK NOTICE: Delete the DTCs after the inspection. (a) Remove the ISCV. (b) CHECK OPERATION (1) Connect the wire harness to the removed ISCV. 2 CHECK THROTTLE BODY IDLE SPEED CONTROL VALVE ASSEMBLY (POWER SOURCE CIRCUIT) RSO B RSC ISCV Vehicle Side Connector A133868 Tester Connection (Terminal Symbol) Standard 2 (B) ←→ 3 (RSC) 9 to 14 V CHECK POWER SOURCE CIRCUIT 3 CHECK WIRE HARNESS OR CONNECTOR (ISC CIRCUIT) RSO B RSC ISC Engine Control Computer ISCV Vehicle Side Connector A133869 Tester Connection (Terminal Symbol) Engine Control Computer ←→ ISCV Standard 65 (ISC) ←→ 1 (RSO) There is continuity and no short between the other terminals and body ground REPAIR OR REPLACE WIRE HARNESS OR CONNECTOR 4 CHECK THROTTLE BODY IDLE SPEED CONTROL VALVE ASSEMBLY
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ES–86 ENGINE CONTROL - EFI SYSTEM (3SZ-VE, K3-VE) ES (2) With the ignition in the ON position, check the operation of the valve. Standard: Neutral (50% open) Fully closed Fully open Neutral (50% open) HINT: Operation should start within 0.5 seconds. NG OK REPLACE THROTTLE BODY IDLE SPEED CONTROL VALVE ASSEMBLY CHECK AND REPLACE ENGINE CONTROL COMPUTER
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ENGINE CONTROL - EFI SYSTEM (3SZ-VE, K3-VE) ES–87 ES DESCRIPTION Cooler thermistor No.1 (evaporator rear sensor) is installed in the evaporator of the air conditioner unit. Cooler thermistor No.1 senses the temperature of the cooled air that has passed through the evaporator as a change in resistance. It outputs this change
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