Smart Access System (Keyless Entry) (Diagnostic Codes & Circuit Tests): Overview Lexus LX J200

DESCRIPTION

This DTC is stored when the IG output circuits inside the main body ECU are open or shorted.

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1. CHECK WHETHER DTC OUTPUT RECURS Clear the DTCs. Refer to «DTC CHECK / CLEAR». Check whether DTC B2271 is output. RESULT Result Proceed to DTC B2271 output A No DTC output B B --> See step 4 A: Go to next step
2. INSPECT FUSE (AM2) Remove the AM2 fuse from the engine room relay block. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition AM2 fuse Always Below 1 ohms NG --> REPLACE FUSE OK: Go to next step
3. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - BATTERY AND BODY GROUND) Disconnect the E1, E2 and 2D main body ECU connectors. Measure the voltage and resistance according to the value(s) in the table below. Standard Voltage Tester Connection Condition Specified Condition E1-6 (AM1) - Body ground Always 11 to 14 V E2-1 (AM2) - Body ground Always 11 to 14 V Standard Resistance Tester Connection Condition Specified Condition 2D-62 (GND2) - Body ground Always Below 1 ohms NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH)
4. USE SIMULATION METHOD TO CHECK. Refer to «HOW TO PROCEED WITH TROUBLESHOOTING»

This DTC is stored when a malfunction occurs in the IG1D output circuit, which is between the IG1 No. 3 relay actuation circuit inside the main body ECU and the IG1 No. 3 relay.

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1. READ VALUE USING TECHSTREAM (IG1 RELAY MONITOR (OUTSIDE)) Use the Data List to check if the IG1 No. 3 relay is functioning properly. MAIN BODY Tester Display Measurement Item/Range Normal Condition Diagnostic Note IG1 Relay Monitor(Outside) IG1 No. 3 relay outer relay monitor/ON or OFF ON: Engine switch on (IG) OFF: Engine switch off - OK When the engine switch is turned on (IG), ON is displayed on the Techstream. NG --> See step 3 OK: Go to next step
2. CHECK WHETHER DTC OUTPUT RECURS Clear the DTCs. Refer to «DTC CHECK / CLEAR». Turn the engine switch on (IG), wait at least 10 seconds, and check whether DTC B2272 is output. RESULT Result Proceed to No DTC output A DTC B2272 output B B --> REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH) A --> See step 4
3. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - BATTERY AND BODY GROUND) Disconnect the E1, 2A and 2D main body ECU connectors. Measure the voltage and resistance according to the value(s) in the table below. Standard Voltage Tester Connection Condition Specified Condition 2A-1 - Body ground Always 11 to 14 V Standard Resistance Tester Connection Condition Specified Condition E1-3 (IG1D) - 2D-43 Always Below 1 ohms 2D-62 (GND2) - Body ground Always Below 1 ohms E1-3 (IG1D) or 2D-43 - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH)
4. USE SIMULATION METHOD TO CHECK. Refer to «HOW TO PROCEED WITH TROUBLESHOOTING»

This DTC is stored when a malfunction occurs in the IG2D output circuit, which is between the integration relay (IG2 relay) actuation circuit inside the main body ECU and the integration relay (IG2 relay).

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1. READ VALUE USING TECHSTREAM (IG2 RELAY MONITOR (INSIDE)) Use the Data List to check if the integration relay (IG2 relay) is functioning properly. MAIN BODY Tester Display Measurement Item/Range Normal Condition Diagnostic Note IG2 Relay Monitor(Inside) Integration relay (IG2 relay) inner relay monitor/ON or OFF ON: Engine switch on (IG) OFF: Engine switch off - OK When the engine switch is turned on (IG), ON is displayed on the Techstream. NG --> See step 3 OK: Go to next step
2. CHECK WHETHER DTC OUTPUT RECURS Clear the DTCs. Refer to «DTC CHECK / CLEAR». Turn the engine switch on (IG), wait at least 10 seconds, and check whether DTC B2273 is output. RESULT Result Proceed to No DTC output A DTC B2273 output B B --> REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH) A --> See step 6
3. INSPECT FUSE (IG2 MAIN) Remove the IG2 MAIN fuse from the integration relay. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition IG2 MAIN fuse Always Below 1 ohms NG --> REPLACE FUSE OK: Go to next step
4. INSPECT INTEGRATION NO. 1 RELAY (IG2 RELAY) Install the IG2 MAIN fuse to the integration relay. Remove the integration relay from the engine room relay block. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition 1B-8 - 1C-1 Battery voltage applied to terminals 1B-6 and 1B-7 Below 1 ohms 1B-8 - 1C-1 Battery voltage not applied to terminals 1B-6 and 1B-7 10 kohms or higher NG --> REPLACE INTEGRATION NO. 1 RELAY OK: Go to next step
5. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY (IG2 RELAY) - MAIN BODY ECU AND BODY GROUND) Disconnect the E2 main body ECU connector. Disconnect the 1B integration relay connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition E2-11 (IG2D) - 1B-6 Always Below 1 ohms 1B-7 - Body ground Always Below 1 ohms E2-11 (IG2D) or 1B-6 - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH)
6. USE SIMULATION METHOD TO CHECK. Refer to «HOW TO PROCEED WITH TROUBLESHOOTING»

This DTC is stored when a malfunction occurs in the ACCD output circuit, which is between the ACC relay actuation circuit inside the main body ECU and the ACC relay.

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1. READ VALUE USING TECHSTREAM (ACC RELAY MONITOR) Use the Data List to check if the ACC relay is functioning properly. MAIN BODY Tester Display Measurement Item/Range Normal Condition Diagnostic Note ACC Relay Monitor ACC relay monitor/ON or OFF ON: Engine switch on (ACC) OFF: Engine switch off - OK When the engine switch is turned on (IG), ON is displayed on the Techstream. NG --> See step 3 OK: Go to next step
2. CHECK WHETHER DTC OUTPUT RECURS Clear the DTCs. Refer to «DTC CHECK / CLEAR». Turn the engine switch on (IG), wait at least 10 seconds, and check whether DTC B2274 is output. RESULT Result Proceed to No DTC output A DTC B2274 output B B --> REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH) A --> See step 4
3. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - BATTERY AND BODY GROUND) Disconnect the E1, 2A and 2D main body ECU connectors. Measure the voltage and resistance according to the value(s) in the table below. Standard Voltage Tester Connection Condition Specified Condition 2A-1 - Body ground Always 11 to 14 V Standard Resistance Tester Connection Condition Specified Condition E1-22 (ACCD) - 2D-45 Always Below 1 ohms 2D-62 (GND2) - Body ground Always Below 1 ohms E1-22 (ACCD) or 2D-45 - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH)
4. USE SIMULATION METHOD TO CHECK. Refer to «HOW TO PROCEED WITH TROUBLESHOOTING»

This DTC is stored when the engine start request signal circuit inside the main body ECU is open or shorted.

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1. CHECK WHETHER DTC OUTPUT RECURS Clear the DTCs. Refer to «DTC CHECK / CLEAR». Depress the brake pedal with the engine switch on (IG), wait at least 15 seconds, and check whether DTC B2275 is output. RESULT Result Proceed to DTC B2275 output A No DTC output B B --> See step 5 A: Go to next step
2. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - ECM) Disconnect the E4 main body ECU connector. Disconnect the A38 ECM connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition E4-4 (STSW) - A38-14 (STSW) Always Below 1 ohms E4-4 (STSW) or A38-14 (STSW) - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
3. INSPECT MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH) Measure the voltage according to the value(s) in the table below. HINT: The voltage is generated at terminal STSW for 0.3 seconds when the engine cranks. Standard Voltage Tester Connection Condition Specified Condition E4-4 (STSW) - Body ground Brake pedal depressed with shift lever in P, engine switch pushed once 11 to 14 V NG --> REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH) OK --> See step 4
4. REPLACE ECM. Refer to «REMOVAL»
5. USE SIMULATION METHOD TO CHECK. Refer to «HOW TO PROCEED WITH TROUBLESHOOTING»

This DTC is stored when a malfunction is detected in the ACCR signal output by the main body ECU.

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1. CHECK WHETHER DTC OUTPUT RECURS Clear the DTCs. Refer to «DTC CHECK / CLEAR». Check whether DTC B2276 is output 50 seconds or more after the engine switch is turned on (IG). RESULT Result Proceed to DTC B2276 output A No DTC output B B --> See step 4 A: Go to next step
2. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - ECM) Disconnect the E2 main body ECU connector. Disconnect the A38 ECM connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition E2-3 (ACCR) - A38-41 (ACCR) Always Below 1 ohms E2-3 (ACCR) or A38-41 (ACCR) - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
3. INSPECT MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH) Measure the voltage according to the value(s) in the table below. Standard Voltage Tester Connection Condition Specified Condition E2-3 (ACCR) - Body ground Engine switch pressed and engine cranking 11 to 14 V NG --> REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH) OK --> See step 5
4. USE SIMULATION METHOD TO CHECK (SYSTEM IS OK). Refer to «HOW TO PROCEED WITH TROUBLESHOOTING»
5. REPLACE ECM. Refer to «REMOVAL»

This DTC is stored when the submersion circuit monitor inside the main body ECU detects that the vehicle has been submerged in water.

This DTC is stored when: 1) a malfunction is detected between the main body ECU and the engine switch; or 2) either of the switches inside the engine switch is malfunctioning.

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1. READ VALUE USING TECHSTREAM (START SWITCH 1, 2) Use the Data List to check if the engine switch is functioning properly. MAIN BODY Tester Display Measurement Item/Range Normal Condition Diagnostic Note Start Switch1 Start switch 1/ON or OFF ON: Engine switch on (IG) OFF: Engine switch off - Start Switch2 Start switch 2/ON or OFF ON: Engine switch on (IG) OFF: Engine switch off - OK When the engine switch is turned on (IG), ON is displayed on the Techstream. NG --> See step 4 OK: Go to next step
2. CHECK WHETHER DTC OUTPUT RECURS Clear the DTCs. Refer to «DTC CHECK / CLEAR». Turn the engine switch on (IG), and check whether DTC B2278 is output. RESULT Result Proceed to No DTC output A DTC B2278 output B B --> REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH) A --> See step 3
3. USE SIMULATION METHOD TO CHECK. Refer to «HOW TO PROCEED WITH TROUBLESHOOTING»
4. INSPECT ENGINE SWITCH Disconnect the E18 engine switch connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Switch Condition Specified Condition 7 (SS1) - 5 (GND) Pushed Below 1 ohms 2 (SS2) - 5 (GND) Pushed Below 1 ohms 7 (SS1) - 5 (GND) Not pushed 10 kohms or higher 2 (SS2) - 5 (GND) Not pushed 10 kohms or higher NG --> See step 6 OK: Go to next step
5. CHECK HARNESS AND CONNECTOR (ENGINE SWITCH - MAIN BODY ECU AND BODY GROUND) Disconnect the E1 main body ECU connector. Disconnect the E18 engine switch connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition E1-17 (SSW1) - E18-7 (SS1) Always Below 1 ohms E1-16 (SSW2) - E18-2 (SS2) Always Below 1 ohms E18-5 (GND) - Body ground Always Below 1 ohms E1-17 (SSW1) or E18-7 (SS1) - Body ground Always 10 kohms or higher E1-16 (SSW2) or E18-2 (SS2) - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH)
6. REPLACE ENGINE SWITCH. Refer to «REMOVAL»(/lexus/lx/j200-2007-2012/remont/starter/#starting-service-information)

This DTC is stored when there is an abnormal circuit between the main body ECU and the shift lock control ECU.

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1. READ VALUE USING TECHSTREAM (SHIFT P SIGNAL) Use the Data List to check if the shift position signal is functioning properly. MAIN BODY Tester Display Measurement Item/Range Normal Condition Diagnostic Note Shift P Signal Shift P position signal/ON or OFF ON: Shift lever in P OFF: Shift lever not in P - RESULT Result Proceed to Display on the Techstream does not change according to shift lever operation A Display on the Techstream changes according to shift lever operation B B --> REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH) A: Go to next step
2. INSPECT SHIFT LOCK CONTROL ECU SUB-ASSEMBLY Disconnect the E51 shift lock control ECU connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition 11 (P2) - 3 (E) Shift lever not in P Below 1 ohms 11 (P2) - 3 (E) Shift lever in P 10 kohms or higher NG --> See step 4 OK: Go to next step
3. CHECK HARNESS AND CONNECTOR (SHIFT LOCK CONTROL ECU - MAIN BODY ECU AND BODY GROUND) Disconnect the E4 main body ECU connector. Disconnect the E51 shift lock control ECU connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition E4-2 (P) - E51-11 (P2) Always Below 1 ohms E51-3 (E) - Body ground Always Below 1 ohms E4-2 (P) or E51-11 (P2) - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH)
4. REPLACE SHIFT LOCK CONTROL ECU SUB-ASSEMBLY. Refer to «DISASSEMBLY - Step 11»

The main body ECU and the combination meter are connected with a cable and the CAN communication line. DTC B2282 is stored when signals, transmitted through the cable and communication line, do not match.

The skid control ECU converts signals from the speed sensor into 4-pulse signals and sends them to the combination meter. After these signals are converted into a more precise rectangular waveform by the waveform shaping circuit inside the combination meter, they are then transmitted to the main body ECU. The main body ECU determines the vehicle speed based on the frequencies of these pulse signals.

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1. READ VALUE USING TECHSTREAM (VEHICLE SPEED SIGNAL) Use the Data List to check if the vehicle speed signal is functioning properly. MAIN BODY Tester Display Measurement Item/Range Normal Condition Diagnostic Note Vehicle Speed Signal Vehicle speed signal/Stop or Run Stop: Vehicle stopped Run: Vehicle running - RESULT Result Proceed to Display on the Techstream does not change according to vehicle condition A Display on the Techstream changes according to vehicle condition B B --> REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH) A: Go to next step
2. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - COMBINATION METER) Disconnect the E3 main body ECU connector. Disconnect the E77 combination meter connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition E3-9 (SPD) - E77-6 (+S) Always Below 1 ohms E3-9 (SPD) or E77-6 (+S) - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
3. REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH) Temporarily replace the main body ECU with a new or normally functioning one. Check whether DTC B2282 and B2283 are output. OK No DTC is output. NG --> See step 4 OK --> END
4. REPLACE COMBINATION METER ASSEMBLY. Refer to «REMOVAL»

This DTC is stored when there is an inconsistency between the circuit between the main body ECU and stop light switch, and the CAN communication signal between the main body ECU and ECM.

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1. READ VALUE USING TECHSTREAM (STOP LIGHT SWITCH) Use the Data List to check if the stop light switch is functioning properly. MAIN BODY Tester Display Measurement Item/Range Normal Condition Diagnostic Note Stop Light SW Stop light switch/ON or OFF ON: Brake pedal depressed OFF: Brake pedal released - RESULT Result Proceed to Display on the Techstream does not change according to brake pedal operation A Display on the Techstream changes according to brake pedal operation B B --> REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH) A: Go to next step
2. INSPECT FUSE (STOP) Remove the STOP fuse from the engine room relay block. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition STOP fuse Always Below 1 ohms NG --> REPLACE FUSE OK: Go to next step
3. INSPECT STOP LIGHT SWITCH ASSEMBLY Disconnect the A30 stop light switch connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Switch Condition Specified Condition 1 - 2 Stop light switch pin not pushed Below 1 ohms 3 - 4 Stop light switch pin pushed Below 1 ohms 1 - 2 Stop light switch pin pushed 10 kohms or higher 3 - 4 Stop light switch pin not pushed 10 kohms or higher NG --> See step 5 OK: Go to next step
4. CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH - BATTERY AND MAIN BODY ECU) Disconnect the 2B main body ECU connector. Disconnect the A30 stop light switch connector. Measure the voltage and resistance according to the value(s) in the table below. Standard Voltage Tester Connection Condition Specified Condition A30-2 - Body ground Always 11 to 14 V Standard Resistance Tester Connection Condition Specified Condition 2B-22 (STP) - A30-1 Always Below 1 ohms 2B-22 (STP) or A30-1 - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH)
5. REPLACE STOP LIGHT SWITCH ASSEMBLY. Refer to «REMOVAL»

The main body ECU and the steering lock ECU are connected by a cable and the LIN communication line. These DTCs are stored when: 1) signals, transmitted through the cable and the communication line, do not match; or 2) a malfunction is detected in the circuit between the main body ECU and the steering lock ECU.

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1. READ VALUE USING TECHSTREAM (STEERING UNLOCK SWITCH) Use the Data List to check if the steering lock is functioning properly. MAIN BODY Tester Display Measurement Item/Range Normal Condition Diagnostic Note Steering Unlock Switch Steering lock condition/ON or OFF ON: Steering unlocked OFF: Steering locked - RESULT Result Proceed to Display on the Techstream does not change according to steering lock position A Display on the Techstream changes according to steering lock position B B --> REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH) A: Go to next step
2. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - STEERING LOCK ECU) Disconnect the E1 main body ECU connector. Disconnect the E26 steering lock ECU connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition E1-18 (SLP) - E26-4 (SLP1) Always Below 1 ohms E1-18 (SLP) or E26-4 (SLP1) - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
3. REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH) Temporarily replace the main body ECU with a new or normally functioning one. Check whether DTC B2285 and B2288 are output. OK No DTC is output. NG --> See step 4 OK --> END
4. REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY). Refer to «DISASSEMBLY»

The main body ECU and ECM are connected by a cable and the CAN communication line. If the cable information and CAN information are inconsistent, this DTC is stored.

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1. READ VALUE USING TECHSTREAM (ENGINE CONDITION) Use the Data List to check if the engine start is functioning properly. MAIN BODY Tester Display Measurement Item/Range Normal Condition Diagnostic Note Engine Condition Engine condition/Stop or Run Stop: Engine stopped Run: Engine running - RESULT Result Proceed to Display on the Techstream does not change according to engine condition A Display on the Techstream changes according to engine condition B B --> REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH) A: Go to next step
2. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - ECM) Disconnect the E3 main body ECU connector. Disconnect the A38 ECM connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition E3-8 (TACH) - A38-15 (TACH) Always Below 1 ohms E3-8 (TACH) or A38-15 (TACH) - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
3. REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH) Temporarily replace the main body ECU with a new or normally functioning one. Check whether DTC B2286 is output. OK No DTC is output. NG --> See step 4 OK --> END
4. REPLACE ECM. Refer to «REMOVAL»

This DTC is stored when there is a LIN communication problem between the main body ECU and certification ECU (smart key ECU assembly) or when there is a problem in the engine immobiliser system.

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1. CHECK WHETHER DTC OUTPUT RECURS Clear the DTCs. Refer to «DTC CHECK / CLEAR». Check whether DTC B2289 is output. RESULT Result Proceed to DTC B2289 output A No DTC output B B --> See step 4 A: Go to next step
2. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)) Disconnect the 2D main body ECU connector. Disconnect the E29 certification ECU (smart key ECU assembly) connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition 2D-20 (LIN1) - E29-10 (LIN) Always Below 1 ohms 2D-20 (LIN1) or E29-10 (LIN) - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
3. REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH) Temporarily replace the main body ECU with a new or normally functioning one. Check whether DTC B2289 is output. OK No DTC is output. NG --> See step 5 OK --> END
4. USE SIMULATION METHOD TO CHECK. Refer to «HOW TO PROCEED WITH TROUBLESHOOTING»
5. REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to «REMOVAL»

When the certification ECU (smart key ECU assembly) has detected the key inside the cabin before the brake pedal is depressed, the power source mode can be changed in the following order sequentially by pressing the engine switch: off --> on (ACC) --> on (IG) --> off.

When one of the DTCs shown in the illustration below is detected, troubleshoot the DTC(s) by following the troubleshooting procedure relevant to the DTC(s). If the power source mode still cannot be changed normally, despite troubleshooting, one of the following may have occurred

1. The LIN communication line is malfunctioning.
2. The certification ECU (smart key ECU assembly) has determined that no key is inside the cabin.
3. The engine switch is malfunctioning.
4. The main body ECU is malfunctioning.

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The engine switch condition (power source mode) or system malfunctions can be checked by observing the status of the engine switch indicator light.

ENGINE SWITCH INDICATOR LIGHT CONDITION

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1. INSPECT ENGINE SWITCH Disconnect the E18 engine switch connector. Apply battery voltage to the terminals of the engine switch, and check the illumination condition of the engine switch indicator light. NOTE: If the positive (+) lead and the negative (-) lead are incorrectly connected, the engine switch indicator light will not illuminate. If the voltage is too low, the indicator light will not illuminate. OK Measurement Condition Condition Specified Condition Battery terminal (+) --> Terminal 11 (SWIL) - Battery terminal (-) --> Terminal 5 (GND) Battery voltage is applied to the terminals Illuminates Battery terminal (+) --> Terminal 12 (INDS) - Battery terminal (-) --> Terminal 5 (GND) Battery terminal (+) --> Terminal 13 (INDW) - Battery terminal (-) --> Terminal 5 (GND) NG --> See step 3 OK: Go to next step
2. CHECK HARNESS AND CONNECTOR (ENGINE SWITCH - MAIN BODY ECU AND BODY GROUND) Disconnect the E1 main body ECU connector. Disconnect the E18 engine switch connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition E1-25 (SWIL) - E18-11 (SWIL) Always Below 1 ohms E1-15 (INDS) - E18-12 (INDS) Always Below 1 ohms E1-14 (INDW) - E18-13 (INDW) Always Below 1 ohms E18-5 (GND) - Body ground Always Below 1 ohms E1-25 (SWIL) or E18-11 (SWIL) - Body ground Always 10 kohms or higher E1-15 (INDS) or E18-12 (INDS) - Body ground Always 10 kohms or higher E1-14 (INDW) or E18-13 (INDW) - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH)
3. REPLACE ENGINE SWITCH. Refer to «REMOVAL»(/lexus/lx/j200-2007-2012/remont/starter/#starting-service-information)

See also:
• REMOVAL