Smart Access System (Keyless Start) (Diagnostic Codes & Symptom Tests): Wiring Lexus IS II facelift

WIRING DIAGRAM

See CRANKING HOLDING FUNCTION CIRCUIT. Refer to Cranking Holding Function Circuit .

Scheme 151

Scheme 152

Scheme 153

Scheme 154

Scheme 155

Scheme 156

Scheme 157

Scheme 158

1. CHECK IF ENGINE START (INITIALIZE STEERING LOCK) Shift lever is in the P position. Open and close the driver's door with the engine switch off. Check if the engine can be started. OK Engine can be started. HINT: After the battery is discharged and then recharged, the engine may not start unless the steering lock is initialized using the above procedure. OK --> END NG: Go to next step
2. CHECK FOR DTC Delete the DTCs. Refer to «DTC CHECK / CLEAR»(ref-387396-S31508654092011022400000) . Check for DTCs again. OK No DTC is output. NG --> GO TO DTC CHART OK: Go to next step
3. CHECK SWITCH CONDITION Check the engine start function. A/T Models: When the key is inside the vehicle and the shift lever is in P, check that pressing the engine switch causes the power source mode to change as follows. M/T Models: When the key is inside the vehicle, check the brake pedal causes the engine to start. OK Engine starts. HINT: If power mode does not change to ON (IG and ACC). Refer to «Power Source Mode does not Change to ON (IG and ACC)»(ref-387397-S34773621942011022400000) . If power mode does not change to ON (IG). Refer to «Power Source Mode does not Change to ON (IG)»(ref-387397-S25856046692011022400000) . If power mode does not change to ON (ACC). Refer to «Power Source Mode does not Change to ON (ACC)»(ref-387397-S42437224122011022400000) . NG --> PROCEED TO APPROPRIATE PROBLEM SYMPTOMS SHOWN IN PROBLEM SYMPTOMS TABLE OK: Go to next step
4. CHECK BASIC FUNCTION Check the engine cranking function. A/T Models: When there is fuel in the fuel tank, the key is inside the vehicle and the shift lever is in P, check that depressing the brake pedal and pressing the engine switch crank the engine. M/T Models: When there is fuel in the tank and the key is inside the vehicle, check that depressing the clutch pedal and the brake pedal and pressing the engine switch crank the engine. OK Engine cranks. NG --> See step 18 OK: Go to next step
5. READ VALUE USING TECHSTREAM (STA SIGNAL) Connect Techstream to the DLC3. Turn the engine switch on (IG). Check the result when the engine switch is turned on (IG) and the engine is started. STANDARD: Engine Switch Position ON (IG) ENGINE START STARTED SIG OFF ON OK ON (ENGINE START) and OFF (ENGINE SWITCH ON (IG)) appear on the screen. OK --> See step 12 NG: Go to next step
6. READ VALUE USING TECHSTREAM (STOP LIGHT SWITCH) Connect Techstream to the DLC3. Turn the engine switch on (IG). Check the DATA LIST for proper functioning of the stop light switch. BODY: Tester Display Measurement Item/Range Normal Condition Diagnostic Note Stop Light SW1 Stop light Switch 1/ ON or OFF ON: Brake pedal depressed OFF: Brake pedal released - OK ON (brake pedal (A/T) or clutch pedal (M/T) depressed) and OFF (brake pedal (A/T) or clutch pedal (M/T) released) appear on the screen. HINT: If the result of the inspection for a tester display is not as specified, perform troubleshooting for DTC B2284 first. Refer to «DTC B2284: Brake Signal Malfunction»(ref-387397-S27225182312011022400000) . NG --> GO TO DTC CHART OK: Go to next step
7. READ VALUE USING TECHSTREAM (STEERING LOCK) Connect Techstream to the DLC3. Turn the engine switch on (IG). BODY: Tester Display Measurement Item/Range Normal Condition Diagnostic Note Steering Unlock Switch Steering lock condition/ ON or OFF ON: Steering is unlocked OFF: Steering is locked - OK ON (steering is unlocked) and OFF (steering is locked) appear on the screen. NG --> See step 22 OK: Go to next step
8. CHECK STEERING LOCK Check if the steering lock is released when turning the engine switch on (ACC). OK The steering lock is released. NG --> GO TO STEERING LOCK SYSTEM OK: Go to next step
9. INSPECT ECM (STAR AND STSW VOLTAGE) Measure the voltage of the A5 and E4 ECM connectors while cranking the engine. Standard voltage Tester Connection Specified Condition STAR (E4-4) - E1 (E4-7) 9 to 14 V STSW (A5-19) - E1 (E4-7) 9 to 14 V Result Terminal STAR Terminal STSW Proceed to 9 to 14 V 9 to 14 V A 0 V 9 to 14 V B 0 V 0 V C C --> See step 16 B --> REPLACE ECM A: Go to next step
10. INSPECT RELAY (ST CUT) Remove the ST CUT relay from the engine room J/B and R/B No. 2. Measure the resistance of the ST CUT relay. Standard resistance Tester Connection Specified Condition 3 - 5 10 kohms or higher 3 - 5 Below 1 ohms (when battery voltage applied to terminals 1 and 2) NG --> REPLACE RELAY OK: Go to next step
11. INSPECT PARK/NEUTRAL POSITION SWITCH (A/T) OR CLUTCH START SWITCH (M/T) Disconnect the park/neutral position (PNP) switch (A/T) or clutch switch (M/T) connector. Measure the resistance between each terminal shown below when the shift lever is moved to each range. Standard resistance (A/T) Shift Position Tester Connection Specified Condition P 4 - 5 Below 1 ohms N 4 - 5 Below 1 ohms Except N or P 4 - 5 10 kohms or higher Standard resistance (M/T) Clutch Pedal Operation Tester Connection Specified Condition Depressed 1 - 2 Below 1 ohms Released 1 - 2 10 kohms or higher NG --> REPLACE PNP SWITCH (A/T) OR CLUTCH START SWITCH (M/T) OK --> CHECK AND REPLACE HARNESS AND CONNECTOR (PARK/NEUTRAL POSITION SWITCH - ECM, ECM - ST CUT RELAY, ST)
12. INSPECT RELAY (STARTER) Remove the starter relay from the engine room J/B and R/B No. 1. Measure the resistance of the starter relay. Standard resistance Tester Connection Specified Condition 3 - 5 10 kohms or higher 3 - 5 Below 1 ohms (when battery voltage applied to terminals 1 and 2) NG --> REPLACE RELAY OK: Go to next step
13. CHECK HARNESS AND CONNECTOR (PNP SWITCH (A/T) OR CLUTCH START SWITCH (M/T) - ST RELAY) Check the harness and the connectors between the park/neutral position switch and the starter relay. Disconnect the E45*1 or A24*2 switch connector. *1: A/T *2: M/T Remove the starter relay from the engine room J/B and R/B No. 1. Measure the resistance of the wire harness side connectors. Standard resistance (A/T) (Check for open) Tester Connection Specified Condition Park/Neutral position switch (E45-5) - Starter relay (1) Below 1 ohms Standard resistance (M/T) (Check for open) Tester Connection Specified Condition Clutch start switch (A24-2) - Starter relay (1) Below 1 ohms Standard resistance (A/T) (Check for short) Tester Connection Specified Condition Park/Neutral position switch (E45-5) or Starter relay (1) - Body ground 10 kohms or higher Standard resistance (M/T) (Check for short) Tester Connection Specified Condition Clutch start switch (A24-2) or Starter relay (1) - Body ground 10 kohms or higher Check the harness and the connector between the starter relay and the body ground. Remove the starter relay from the engine room J/B and R/B No. 1. Measure the resistance of the starter relay and the body ground. Standard resistance (Check for open) Tester Connection Specified Condition Starter relay (2) - Body ground Below 1 ohms NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
14. INSPECT ENGINE ROOM RELAY BLOCK (STARTER RELAY VOLTAGE) Remove the starter relay from the engine room J/B and R/B No. 1. Measure the voltage of the engine room J/B and R/B No. 1 and the body ground. Standard voltage Tester Connection Specified Condition Starter relay (5) - Body ground 9 to 14 V NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
15. INSPECT STARTER ASSEMBLY HINT: Refer to «INSPECTION»(ref-387362-S36855195162011022400000) . NG --> REPAIR OR REPLACE STARTER ASSEMBLY OK --> REPAIR OR REPLACE HARNESS OR CONNECTOR (STARTER RELAY - STARTER, STARTER - BATTERY)
16. CHECK HARNESS AND CONNECTOR (POWER SOURCE CONTROL ECU - ECM) Check the harness and the connectors between the power source control ECU and ECM. Disconnect the power source control ECU connector. Disconnect the A5 ECM connector. Measure the resistance of the wire harness side connectors. Standard resistance (Check for open) Tester Connection Specified Condition J55-39 (STSW) - A5-19 (STSW) Below 1 ohms Standard resistance (Check for short) Tester Connection Specified Condition J55-39 (STSW) or A5-19 (STSW) - Body ground 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
17. CHECK AND REPLACE POWER SOURCE CONTROL ECU Replace the power source control ECU. Check the engine cranking function. A/T Models: When there is fuel in the fuel tank, the key is inside the vehicle and the shift lever is in P, check that depressing the brake pedal and pressing the engine switch crank the engine. M/T Models: When there is fuel in the tank and the key is inside the vehicle, check that depressing the clutch pedal and the brake pedal and pressing the engine switch crank the engine. OK Engine cranks. HINT: After the power source control ECU is replaced, the engine may not start unless each system is initialized using the above procedure. NG --> REPLACE ECM OK --> END
18. READ VALUE USING TECHSTREAM (L CODE) Reconnect the connectors. Connect Techstream to the DLC3. Turn the engine switch on (IG). SMART ACCESS: Tester Display Measurement Item/Range Normal Condition Diagnostic Note L Code Check L code check/ ON or NG OK: Normal NG: Malfunction Electrical key in the cabin OK OK is displayed on the screen. HINT: If the result of the inspection for a tester display is not as specified, there may be malfunction of the steering lock ECU or the ID code box. NG --> GO TO ENGINE IMMOBILISER SYSTEM OK: Go to next step
19. READ VALUE USING TECHSTREAM (ENGINE START REQUEST) Connect Techstream to the DLC3. Turn the engine switch on (IG). SMART ACCESS: Tester Display Measurement Item/Range Normal Condition Diagnostic Note Starter Request Signal Start request signal response/ OK or NG OK: Received NG: Non-received - OK OK (received) and NG (non-received) appear on the screen. NG --> REPLACE CERTIFICATION ECU OK: Go to next step
20. READ VALUE USING TECHSTREAM (S CODE) Connect Techstream to the DLC3. Turn the engine switch on (IG). SMART ACCESS: Tester Display Measurement Item/Range Normal Condition Diagnostic Note S Code Check S code check/ OK or NG OK: Normal NG: Malfunction - OK OK is displayed on the screen. HINT: If the result of the inspection for a tester display is not as specified, there may be malfunction of the certification ECU or the ID code box. NG --> GO TO ENGINE IMMOBILISER SYSTEM OK: Go to next step
21. INSPECT ID CODE BOX Check the input signal waveform. Connect the oscilloscope to the terminals J69-6 (EFIO) and A6-6 (IMI). Turn the engine switch on (IG). Check the signal waveform according to the condition(s) in the table below. Item Condition Tool setting 10 V/DIV., 100 ms./DIV. Vehicle condition Engine switch on (IG) NG --> REPLACE ID CODE BOX OK --> END
22. CHECK WIRE HARNESS (POWER SOURCE CONTROL ECU - STEERING LOCK ECU) Disconnect the ECU connector. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Connection (Symbols) Specified Condition J55-26 (SLP) - J29-4 (SLP1) Below 1 ohms J55-26 (SLP) or J29-4 (SLP1) - Body ground 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
23. INSPECT POWER SOURCE CONTROL ECU Reconnect the J55 ECU connector. Connect the oscilloscope to the power source control ECU terminals specified in the table below and check the waveform. Item Contents Terminal (Symbols) J55-26 (SLP) - Body ground Equipment Setting 2 V/DIV., 100 ms./DIV. Condition Engine switch on (IG) OK The waveform appears as shown in the illustration. HINT: The waveform varies depending on the contents of communication. NG --> REPLACE POWER SOURCE CONTROL ECU OK: Go to next step
24. INSPECT STEERING LOCK ECU Reconnect the J29 ECU connector. Connect the oscilloscope to the power source control ECU terminals specified in the table below and check the waveform. Item Contents Terminal (Symbols) J55-26 (SLP) - Body ground Equipment Setting 2 V/DIV., 100 ms./DIV. Condition Steering is LOCK / UNLOCK OK The waveform appears as shown in the illustration. HINT: The waveform varies depending on the contents of communication. NG --> REPLACE STEERING LOCK ECU OK --> REPLACE POWER SOURCE CONTROL ECU