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Multiplex Communication System - Diagnostics: Diagnosis Lexus GX J120

Communication Devices 71 illustrations ~4155 words

HOW TO PROCEED WITH TROUBLESHOOTING

HINT

Troubleshoot in accordance with the procedures on the following references.

  1. VEHICLE BROUGHT TO WORKSHOP Go to next step.
  2. CUSTOMER PROBLEM ANALYSIS CHECK AND SYMPTOM CHECK (See «PROBLEM SYMPTOMS TABLE»(ref-228774-S37628537642006041100000) ) Go to next step.
  3. DTC CHECK (See «DIAGNOSTIC TROUBLE CODE TABLE»(ref-228774-S25387993042006041100000) ) Check for DTC and make a note of the code that is output. Delete the DTC. Check if the DTC will be output once again when the problem symptom is simulated based on the noted code. When no code is output (symptom check and simulation are possible), proceed to A. When a code is output, proceed to B. B: Go to step 6 . A: Go to next step.
  4. See «PROBLEM SYMPTOMS TABLE»(ref-228774-S37628537642006041100000) Without applicable symptoms, proceed to A. With applicable symptoms, proceed to B. B: Go to step 6 . A: Go to next step.
  5. PERFORM TROUBLESHOOTING IN FOLLOWING METHOD, DEPENDING ON MALFUNCTION SYMPTOM See «PRE-CHECK»(ref-228774-S35362889612006041100000) See «TERMINALS OF ECU»(ref-228774-S15148433662006041100000)
  6. ADJUST, REPAIR OR REPLACE Go to next step. END

DIAGNOSTIC TROUBLE CODE TABLE

If a malfunction code is displayed during the DTC check, check the circuit listed for that code in DIAGNOSTIC TROUBLE CODE TABLE .

DTCDescription
DTC B1211DRIVER DOOR ECU COMMUNICATION STOP
DTC B1213TILT AND TELESCOPIC ECU COMMUNICATION STOP
DTC B1214, B1215DOOR SYSTEM COMMUNICATION BUS MALFUNCTION (+B SHORT)/(GND SHORT)
DTC B1218BODY NO.2 ECU COMMUNICATION STOP
DTC B1245WIPER ECU COMMUNICATION STOP
DTC B1269THEFT DETERRENT ECU COMMUNICATION STOP
DTC B1272POWER SEAT ECU COMMUNICATION STOP
DTC B1276A/C AND METER ECU (MIRROR) COMMUNICATION STOP
DTC B1279RAIN SENSOR COMMUNICATION STOP

DIAGNOSTIC TROUBLE CODE TABLE

Scheme 75

Scheme 75: LOCATION
Scheme 75: LOCATION

Scheme 76

Scheme 76: TERMINALS OF ECU
Scheme 76: TERMINALS OF ECU

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  1. CHECK INSTRUMENT PANEL JUNCTION BLOCK ASSY (BODY ECU) Disconnect the IB, IE and IH J/B connectors. Check the voltage or continuity of each terminal of the wire harness side connectors. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Wiring Color Condition Specified Condition BECU (IB-4) <--> Body ground W-R <--> - Constant 10 - 14 V BDR1 (IE-9) <--> Body ground G-W <--> - Constant 10 - 14 V GND1 (IH-2) <--> Body ground W-B <--> - Constant Continuity GND2 (IH-2) <--> Body ground W-B <--> - Constant Continuity If the result is not as specified, there may be a malfunction on the wire harness side.
  2. CHECK POWER WINDOW REGULATOR MASTER SWITCH ASSY (DRIVER DOOR ECU) Disconnect the D18 switch connector. Check the voltage or continuity of each terminal of the wire harness side connector. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Wiring Color Condition Specified Condition E (D18-2) <--> Body ground W-B <--> - Constant Continuity CPUB (D18-9) <--> E (D18-2) L <--> W-B Constant 10 - 14 V BDR1 (D18-10) <--> E (D18-2) B-W <--> W-B Constant 10 - 14 V If the result is not as specified, there may be a malfunction on the wire harness side.
  3. CHECK MULTIPLEX TILT & TELESCOPIC ECU (TILT & TELESCOPIC ECU) Disconnect the T6 ECU connector. Check the voltage or continuity of each terminal of the wire harness side connector. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Wiring Color Condition Specified Condition GND (T6-11) <--> Body ground W-G <--> - Constant Continuity +B (T6-2) <--> GND (T6-11) G-B <-->W-G Constant 10 - 14 V ECUB (T6-9) <--> GND (T6-11) W-R <--> W-G Constant 10 - 14 V If the result is not as specified, there may be a malfunction on the wire harness side.
  4. CHECK MULTIPLEX NETWORK BODY ECU NO. 2 (BODY NO. 2 ECU) Disconnect the S27 ECU connector. Check the voltage or continuity of each terminal of the wire harness side connector. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Wiring Color Condition Specified Condition GND (S27-25) <--> Body ground W-B <--> - Constant Continuity SG (S27-24) <--> GND (S27-25) W-B <--> W-B Constant Continuity SIG (S27-3) <--> GND (S27-25) B-R <--> W-B Constant Continuity BECU (S27-4) <--> GND (S27-25) W-R <--> W-B Constant 10 - 14 V If the result is not as specified, there may be a malfunction on the wire harness side.
  5. CHECK WINDSHIELD WIPER ECU (WIPER ECU) Disconnect the W4 and W5 ECU connectors. Check the voltage or continuity of each terminal of the wire harness side connectors. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Wiring Color Condition Specified Condition GND (W4-12) <--> Body ground W-B <--> - Constant Continuity WIG (W5-10) <--> Body ground L <--> - Constant Continuity +B (W4-8) <--> GND (W4-12) W-R <--> W-B Constant 10 - 14 V If the result is not as specified, there may be a malfunction on the wire harness side.
  6. CHECK THEFT WARNING ECU ASSY (THEFT DETERRENT ECU) Disconnect the T5 ECU connector. Check the voltage or continuity of each terminal of the wire harness side connector. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Wiring Color Condition Specified Condition E (T5-29) <--> Body ground W-B <--> - Constant Continuity +B1 (T5-2) <--> E (T5-29) W-R <--> W-B Constant 10 - 14 V +B2 (T5-3) <--> E (T5-29) P <--> W-B Constant 10 - 14 V If the result is not as specified, there may be a malfunction on the wire harness side.
  7. CHECK POSITION CONTROL ECU & WIRING ASSY (POWER SEAT ECU) Disconnect the P19 and P20 ECU connectors. Check the voltage or continuity of each terminal of the wire harness side connectors. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Wiring Color Condition Specified Condition GND (P19-1) <--> Body ground W-B <--> - Constant Continuity +B (P19-5) <--> GND (P19-1) LG <--> W-B Constant 10 - 14 V SYSB (P20-8) <--> GND (P19-1) GR <--> W-B Constant 10 - 14 V If the result is not as specified, there may be a malfunction on the wire harness side.
  8. CHECK OUTER MIRROR CONTROL ECU ASSY (MIRROR ECU) Disconnect the R10 ECU connector. Check the voltage or continuity of each terminal of the wire harness side connector. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Wiring Color Condition Specified Condition GND (R10-14) <--> Body ground W-B <--> - Constant Continuity +B (R10-1) <--> GND (R10-14) W-R <--> W-B Constant 10 - 14 V If the result is not as specified, there may be a malfunction on the wire harness side.
  9. CHECK RAIN SENSOR Disconnect the R13 ECU connector. Check the voltage or continuity of each terminal of the wire harness side connector. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Wiring Color Condition Specified Condition ES (R13-3) <--> Body ground W-B <--> - Constant Continuity SIG (R13-1) <--> ES (R13-3) B-W <--> W-B Constant 10 - 14 V If the result is not as specified, there may be a malfunction on the wire harness side.

Scheme 85

Scheme 85: PROBLEM SYMPTOMS TABLE
Scheme 85: PROBLEM SYMPTOMS TABLE
  1. TROUBLESHOOTING FOR EACH PROBLEM SYMPTOM NOTE: Confirm the problem symptom and make an inspection depending on (Scheme 85).

CIRCUIT DESCRIPTION

DTC B1211 is output when the communication between the driver door ECU and the body ECU stops for more than 10 seconds.

Scheme 86

Scheme 86: CIRCUIT DESCRIPTION
Scheme 86: CIRCUIT DESCRIPTION

Scheme 87

Scheme 87: WIRING DIAGRAM
Scheme 87: WIRING DIAGRAM

Scheme 88

Scheme 88: INSPECTION PROCEDURE
Scheme 88: INSPECTION PROCEDURE

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Scheme 89

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Scheme 90
Scheme 90
  1. CHECK CONTINUITY OF COMMUNICATION LINE Disconnect the D18 master switch, B3 J/B and S28 ECU connectors. Check the continuity between the wire harness side connectors. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Specified Condition MPX1 (D18-7) <--> MPX1 (B3-24) Continuity MPX2 (D18-8) <--> MPX+ (S28-2) Continuity NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: Go to next step.
  2. CHECK POWER WINDOW REGULATOR MASTER SWITCH ASSY (DRIVER DOOR ECU) (POWER SOURCE) Disconnect the D18 master switch connector. Check the voltage between the wire harness side connector and body ground. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Specified Condition CPUB (D18-9) <--> Body ground 10 - 14 V BDR1 (D18-10) <--> Body ground 10 - 14 V NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: Go to next step.
  3. CHECK POWER WINDOW REGULATOR MASTER SWITCH ASSY (DRIVER DOOR ECU) (GROUND) Disconnect the D18 master switch connector. Check the continuity between the wire harness side connector and body ground. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Specified Condition E (D18-2) <--> Body ground Continuity NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: REPLACE POWER WINDOW REGULATOR MASTER SWITCH ASSY

DTC B1213 is output when communication between the multiplex tilt & telescopic ECU and the body ECU stops for more than 10 seconds.

Scheme 91

Scheme 91: CIRCUIT DESCRIPTION
Scheme 91: CIRCUIT DESCRIPTION

Scheme 92

Scheme 92: WIRING DIAGRAM
Scheme 92: WIRING DIAGRAM

Scheme 93

Scheme 93: INSPECTION PROCEDURE
Scheme 93: INSPECTION PROCEDURE

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Scheme 95
  1. CHECK CONTINUITY OF COMMUNICATION LINE Disconnect the T6 ECU and B3 J/B connectors. Check the continuity between the wire harness side connectors. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Specified Condition MPX2 (T6-14) <--> MPX2 (B3-23) Continuity NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: Go to next step.
  2. CHECK MULTIPLEX TILT & TELESCOPIC ECU Disconnect the T6 ECU connector. Check the voltage between the wire harness side connector and body ground. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Specified Condition ECUB (T6-9) <--> Body ground 10 - 14 V +B (T6-2) <--> Body ground 10 - 14 V NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: Go to next step.
  3. CHECK MULTIPLEX TILT & TELESCOPIC ECU Disconnect the T6 ECU connector. Check the continuity between the wire harness side connector and body ground. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Specified Condition GND (T6-11) <--> Body ground Continuity NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: REPLACE MULTIPLEX TILT & TELESCOPIC ECU

B1214 and B1215 are output when +B and the body ground is short-circuited on the communication bus. Detecting this condition disables all the BEAN communication and outputs some DTCs.

Scheme 96

Scheme 96: CIRCUIT DESCRIPTION
Scheme 96: CIRCUIT DESCRIPTION

Scheme 97

Scheme 97: WIRING DIAGRAM
Scheme 97: WIRING DIAGRAM

Scheme 98

Scheme 98: INSPECTION PROCEDURE
Scheme 98: INSPECTION PROCEDURE

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Scheme 115
  1. CHECK DTC (BODY ECU <--> POWER SEAT ECU) Check whether the output of the DTC stops when the B3 connector of the body ECU is disconnected. NOTE: Disconnect connector in operational sequence, and start the next operation after the connector is connected. Standard: When the output of the DTC stops, there is a malfunction between the B3 connector of the body ECU and the power seat ECU. NO: Go to step 6 . YES: Go to next step.
  2. CHECK DTC (POWER SEAT ECU) Check whether the output of the DTC stops when the power seat ECU connector is disconnected. NOTE: Disconnect connector in operational sequence, and start the next operation after the connector is connected. Standard: When the output of the DTC stops, the power seat ECU is abnormal. YES: REPLACE POSITION CONTROL ECU & SWITCH ASSY (POWER SEAT ECU) NO: Go to next step.
  3. CHECK DTC (MIRROR ECU AND WIRE HARNESS) Check whether the output of the DTC stops when the mirror ECU connector is disconnected. NOTE: Disconnect connectors in operational sequence, and start the next operation after the connector is connected. Standard: When the output of the DTC stops, the mirror ECU itself or the wire harness between the mirror ECU and the power seat ECU is abnormal. YES: REPAIR OR REPLACE OUTER MIRROR CONTROL ECU ASSY (MIRROR ECU) OR WIRE HARNESS NO: Go to next step.
  4. CHECK DTC (TILT & TELESCOPIC ECU) Check whether the output of the DTC stops when the tilt and telescopic ECU connector is disconnected. NOTE: Disconnect connectors in operational sequence, and start the next operation after the connector connected. Standard: When the output of the DTC stops, the tilt & telescopic ECU itself or the wire harness between the tilt and telescopic ECU and the mirror ECU is abnormal. YES: REPAIR OR REPLACE MULTIPLEX TILT & TELESCOPIC ECU (TILT & TELESCOPIC ECU) OR WIRE HARNESS NO: Go to next step.
  5. CHECK WIRE HARNESS (BODY ECU <--> TILT & TELESCOPIC ECU) Check whether the output of the DTC stops when the wire harness is disconnected. NOTE: Disconnect connectors in operational sequence, and start the next operation after the connector is connected. Standard: When the output of the DTC stops, the wire harness between the B3 connector of the body ECU and the tilt and telescopic ECU is abnormal. YES: REPAIR OR REPLACE HARNESS AND CONNECTOR NO: Go to next step.
  6. CHECK DTC (BODY ECU <--> J/B) Check whether the output of the DTCs stops when the B3 connector of the body ECU and 1B connector of the junction block are disconnected. NOTE: Disconnect connectors in operational sequence, and start the next operation after the connector is connected. Standard: When the output of the DTC stops, there is a malfunction between the B3 connector of the body ECU and the 1B connector of the junction block. NO: Go to step 12 . YES: Go to next step.
  7. CHECK DTC (DRIVER DOOR ECU) Check whether the output of the DTC stops when the driver door ECU connector is disconnected. NOTE: Disconnect connector in operational sequence, and start the next operation after the connector is connected. Standard: When the output of the DTC stops, the driver door ECU is abnormal. YES: REPLACE POWER WINDOW REGULATOR MASTER SWITCH ASSY (DRIVER DOOR ECU) NO: Go to next step.
  8. CHECK WIRE HARNESS (BODY ECU <--> DRIVER DOOR ECU) Check whether the output of the DTC stops when the B3 connector of the body ECU and the driver door ECU connector are disconnected. NOTE: Disconnect connectors in operational sequence, and start the next operation after the connector is connected. Standard: When the output of the DTC stops, the wire harness between the driver door ECU and B3 connector of the body ECU is abnormal. YES: REPAIR OR REPLACE HARNESS AND CONNECTOR NO: Go to next step.
  9. CHECK DTC (BODY NO.2 ECU) Check whether the output of the DTC stops when the body No.2 ECU connector is disconnected. NOTE: Disconnect connectors in operational sequence, and start the next operation after the connector is connected. Standard: When the output of the DTC stops, the body No.2 ECU is abnormal. YES: REPLACE MULTIPLEX NETWORK BODY ECU NO.2 (BODY NO. 2 ECU) NO: Go to next step.
  10. CHECK WIRE HARNESS (BODY No.2 ECU <--> DRIVER DOOR ECU) Check whether the output of the DTC stops when the B3 connector of the body ECU and the body No.2 ECU connector are disconnected. NOTE: Disconnect connectors in operational sequence, and start the next operation after the connector is connected. Standard: When the output of the DTC stops, the wire harness between the body No.2 ECU and the driver door ECU is abnormal. YES: REPAIR OR REPLACE HARNESS AND CONNECTOR NO: Go to next step.
  11. CHECK WIRE HARNESS (J/B <--> BODY No.2 ECU) Check whether the output of the DTC stops when the B3 connector of the body ECU and the 1B connector of the J/B No.1 are disconnected. NOTE: Disconnect connectors in operational sequence, and start the next operation after the connector is connected. Standard: When the output of the DTC stops, the wire harness between the 1B connector of the J/ B (No.1) and the body No.2 ECU is abnormal. YES: REPAIR OR REPLACE HARNESS AND CONNECTOR NO: Go to next step.
  12. CHECK DTC (THEFT DETERRENT ECU) Check whether the output of the DTC stops when the theft deterrent ECU connector is disconnected. NOTE: Disconnect connectors in operational sequence, and start the next operation after the connector is connected. Standard: When the output of the DTC stops, the theft deterrent ECU is abnormal. YES: REPLACE THEFT WARNING ECU ASSY (THEFT DETERRENT ECU) NO: Go to next step.
  13. CHECK WIRE HARNESS (J/B <--> THEFT DETERRENT ECU) Check whether the output of the DTC stops when the 1A connector of the J/B (No.1) is disconnected. NOTE: Disconnect connectors in operational sequence, and start the next operation after the connector is connected. Standard: When the output of the DTC stops, the wire harness between the 1A connector of the J/B No.1 and the theft deterrent ECU is abnormal. YES: REPAIR OR REPLACE HARNESS AND CONNECTOR NO: Go to next step.
  14. CHECK DTC (RAIN SENSOR) Check whether the output of the DTC stops when the rain sensor connector is disconnected. NOTE: Disconnect connectors in operational sequence, and start the next operation after the connector is connected. Standard: When the output of the DTC stops, the rain sensor is abnormal. YES: REPLACE RAIN SENSOR NO: Go to next step.
  15. CHECK DTC (WIPER ECU OR WIRE HARNESS (WIPER ECU <--> RAIN SENSOR)) Check whether the output of the DTC stops when the wiper ECU connector is disconnected. NOTE: Disconnect connectors in operational sequence, and start the next operation after the connector is connected. Standard: When the output of the DTC stops, the wiper ECU or the wire harness between the wiper ECU and the rain sensor is abnormal. YES: REPAIR OR REPLACE WINDSHIELD WIPER ECU (WIPER ECU) OR WIRE HARNESS NO: Go to next step.
  16. CHECK WIRE HARNESS (J/B <--> WIPER ECU) Check whether the output of the DTC stops when the 1C connector of the J/B is disconnected. NOTE: Disconnect connectors in operational sequence, and start the next operation after the connector is connected. Standard: When the output of the DTC stops, the wire harness between the 1C connector of the J/B (No.1) and the wiper ECU is abnormal. YES: REPAIR OR REPLACE HARNESS AND CONNECTOR NO: Go to next step.
  17. CHECK DTC (J/B) Check whether the output of the DTC stops when the J/B is disconnected. NOTE: Disconnect connectors in operational sequence, and start the next operation after the connector is connected. Standard: When the output of the DTC stops, the J/B (No.1) is abnormal. YES: REPLACE JUNCTION BLOCK (No.1) NO: Go to next step.
  18. CHECK DTC (BODY ECU OR WIRE HARNESS (BODY ECU <--> J/B)) Check whether the output of the DTC stops when the body ECU is disconnected. NOTE: Disconnect connectors in operational sequence, and start the next operation after the connector is connected. Standard: When the output of the DTC stops, the body ECU or the wire harness between the B5 connector of the body ECU and the 1A connector of the J/B (No.1) is abnormal. YES: REPAIR OR REPLACE HARNESS AND CONNECTOR NO: REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSY (BODY ECU)

DTC B1218 is output when the communication between the body No.2 ECU and the body ECU stops for more than 10 seconds.

Scheme 116

Scheme 116: CIRCUIT DESCRIPTION
Scheme 116: CIRCUIT DESCRIPTION

Scheme 117

Scheme 117: WIRING DIAGRAM
Scheme 117: WIRING DIAGRAM

Scheme 118

Scheme 118: INSPECTION PROCEDURE
Scheme 118: INSPECTION PROCEDURE

Scheme 119

Scheme 119
Scheme 119

Scheme 120

Scheme 120
Scheme 120
  1. CHECK CONTINUITY OF COMMUNICATION LINE Disconnect the S28 ECU and D18 master switch connectors. Check the continuity between the wire harness side connectors. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Specified Condition MPX+ (S28-2) <--> MPX2 (D18-8) Continuity MPX- (S28-6) <--> MPX3 (B5-26) Continuity NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: Go to next step.
  2. CHECK MULTIPLEX NETWORK BODY ECU NO.2 (BODY No.2 ECU) (POWER SOURCE) Disconnect the S27 ECU connector. Check the voltage between the wire harness side connector and body ground. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Specified Condition BECU (S27-4) <--> Body ground 10 - 14 V SIG (S27-3) <--> Body ground 10 - 14 V NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: Go to next step.
  3. CHECK MULTIPLEX NETWORK BODY ECU NO.2 (GROUND) (BODY No.2 ECU) Disconnect the S27 ECU connector. Check the continuity between the wire harness side connector and body ground. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Specified Condition SG (S27-24) <--> Body ground Continuity GND (S27-25) <--> Body ground Continuity NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: REPLACE MULTIPLEX NETWORK BODY ECU NO.2

DTC B1245 is output when the communication between the wiper ECU and the body ECU stops for more than 10 seconds.

Scheme 121

Scheme 121: CIRCUIT DESCRIPTION
Scheme 121: CIRCUIT DESCRIPTION

Scheme 122

Scheme 122: WIRING DIAGRAM
Scheme 122: WIRING DIAGRAM

Scheme 123

Scheme 123: INSPECTION PROCEDURE
Scheme 123: INSPECTION PROCEDURE

Scheme 124

Scheme 124
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Scheme 125
Scheme 125
  1. CHECK CONTINUITY OF COMMUNICATION LINE Disconnect the W4 ECU, R13 rain sensor and B5 J/B connectors. Check the continuity between the wire harness side connectors. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Specified Condition MPX2 (W4-2) <--> MPX3 (B5-26) Continuity MPX1 (W4-1) <--> MPX (R13-2) Continuity NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: Go to next step.
  2. CHECK WINDSHIELD WIPER ECU (WIPER ECU) (POWER SOURCE) Disconnect the W4 and W5 ECU connectors. Check the voltage between the wire harness side connector and body ground. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Specified Condition +B (W4-8) <--> Body ground 10 - 14 V WIG (W5-10) <--> Body ground 10 - 14 V NG: REPAIR OR REPLACE FUSE OR HARNESS AND CONNECTOR OK: Go to next step.
  3. CHECK WINDSHIELD WIPER ECU (WIPER ECU) (GROUND) Disconnect the W4 ECU connector. Check the continuity between the wire harness side connector and body ground. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Specified Condition GND (W4-12) <--> Body ground Continuity NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: REPLACE WINDSHIELD WIPER ECU

DTC B1269 is output when the communication between the theft deterrent ECU and the body ECU stops for more than 10 seconds.

Scheme 126

Scheme 126: CIRCUIT DESCRIPTION
Scheme 126: CIRCUIT DESCRIPTION

Scheme 127

Scheme 127: WIRING DIAGRAM
Scheme 127: WIRING DIAGRAM

Scheme 128

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Scheme 130
Scheme 130
  1. REPLACE CONTINUITY OF COMMUNICATION LINE Disconnect the T5 ECU and B5 J/B connectors. Check the continuity between wire harness side connectors. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Specified Condition MPX1 (T5-31) <--> MPX3 (B5-26) Continuity NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: Go to next step.
  2. CHECK THEFT WARNING ECU ASSY (THEFT DETERRENT ECU) (POWER SOURCE) Disconnect the T5 ECU connector. Check the voltage between the wire harness side connector and body ground. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Specified Condition +B1 (T5-2) <--> Body ground 10 - 14 V +B2 (T5-3) <--> Body ground 10 - 14 V NG: REPAIR OR REPLACE FUSE OR HARNESS AND CONNECTOR OK: Go to next step.
  3. CHECK THEFT WARNING ECU ASSY (THEFT DETERRENT ECU) (GROUND) Disconnect the T5 ECU connector. Check the continuity between the wire harness side connector and body ground. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Specified Condition E (T5-29) <--> Body ground Continuity NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: REPLACE THEFT WARNING ECU ASSY

DTC B1272 is output when the communication between the power seat ECU and the body ECU stops for more than 10 seconds.

Scheme 131

Scheme 131: CIRCUIT DESCRIPTION
Scheme 131: CIRCUIT DESCRIPTION

Scheme 132

Scheme 132: WIRING DIAGRAM
Scheme 132: WIRING DIAGRAM

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Scheme 133: INSPECTION PROCEDURE
Scheme 133: INSPECTION PROCEDURE

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  1. CHECK CONTINUITY OF COMMUNICATION LINE Disconnect the P20 switch and R10 ECU connectors. Check the continuity between the wire harness side connectors. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Specified Condition MPX1 (P20-1) <--> MPX2 (R10-25) Continuity NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: Go to next step.
  2. CHECK FRONT POWER SEAT SWITCH (POWER SEAT ECU) (POWER SOURCE) Disconnect the P19 and P20 switch connectors. Check the voltage between the wire harness side connector and body ground. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Specified Condition +B (P19-5) <--> Body ground 10 - 14 V SYSB (P20-8) <--> Body ground 10 - 14 V NG: REPAIR OR REPLACE FUSE OR HARNESS AND CONNECTOR OK: Go to next step.
  3. CHECK FRONT POWER SEAT SWITCH (DRIVER DOOR ECU) (GROUND) Disconnect the P19 switch connector. Check the continuity between the wire harness side connector and body ground. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Specified Condition GND (P19-1) <--> Body ground Continuity NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: REPLACE FRONT POWER SEAT SWITCH

DTC B1276 is output when the communication between the mirror ECU and the body ECU stops for more than 10 seconds.

Scheme 136

Scheme 136: CIRCUIT DESCRIPTION
Scheme 136: CIRCUIT DESCRIPTION

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Scheme 137: WIRING DIAGRAM
Scheme 137: WIRING DIAGRAM

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Scheme 140
  1. CHECK CONTINUITY OF COMMUNICATION LINE Disconnect the R10, T6 and P20 ECU connectors. Check the continuity between the wire harness side connectors. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Specified Condition MPX1 (R10-13) <--> MPX1 (T6-5) Continuity MPX2 (R10-25) <--> MPX1 (P20-1) Continuity NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: Go to next step.
  2. CHECK OUTER MIRROR CONTROL ECU ASSY (MIRROR ECU) (POWER SOURCE) Disconnect the R10 ECU connector. Check the voltage between the wire harness side connector and body ground. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Specified Condition +B (R10-1) <--> Body ground 10 - 14 V NG: REPAIR OR REPLACE FUSE OR HARNESS AND CONNECTOR OK: Go to next step.
  3. CHECK OUTER MIRROR CONTROL ECU ASSY (MIRROR ECU) (GROUND) Disconnect the R10 ECU connector. Check the continuity between the wire harness side connector and body ground. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Specified Condition GND (R10-14) <--> Body ground Continuity NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: REPLACE OUTER MIRROR CONTROL ECU ASSY

DTC B1279 is output when the communication between the rain sensor and the body ECU stops for more than 10 seconds.

Scheme 141

Scheme 141: CIRCUIT DESCRIPTION
Scheme 141: CIRCUIT DESCRIPTION

Scheme 142

Scheme 142: WIRING DIAGRAM
Scheme 142: WIRING DIAGRAM

Scheme 143

Scheme 143: INSPECTION PROCEDURE
Scheme 143: INSPECTION PROCEDURE

Scheme 144

Scheme 144
Scheme 144

Scheme 145

Scheme 145
Scheme 145
  1. CHECK CONTINUITY OF COMMUNICATION LINE Disconnect the R13 rain sensor W4 ECU connectors. Check the continuity between the wire harness side connectors. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Specified Condition MPX (R13-2) <--> MPX1 (W4-1) Continuity NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: Go to next step.
  2. CHECK RAIN SENSOR (POWER SOURCE) Disconnect the R13 rain sensor connector. Check the voltage between the wire harness side connector and body ground. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Specified Condition SIG (R13-1) <=> Body ground 10 - 14 V NG: REPAIR OR REPLACE FUSE OR HARNESS AND CONNECTOR OK: Go to next step.
  3. CHECK RAIN SENSOR (GROUND) Disconnect the R13 rain sensor connector. Check the continuity between the wire harness side connector and body ground. Standard: TERMINAL SPECIFIED CONDITION Symbols (Terminal No.) Specified Condition ES (R13-3) <=> Body ground Continuity NG: REPAIR OR REPLACE HARNESS AND CONNECTOR OK: REPLACE RAIN SENSOR

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