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Contents Wiring diagrams Section: Communication Devices All sections

Multiplex Communication System (Diagnostic Codes): Other Lexus IS II facelift 2

Communication Devices ~5127 words

PROCEDURE

  1. INSPECT FUSE (FR DOOR RH) Remove the FR DOOR RH fuse from the cowl side J/B RH. Measure the resistance of the fuse. Standard resistance Below 1 ohms NG --> REPLACE FUSE OK: Go to next step
  2. CHECK WIRE HARNESS (MAIN BODY ECU RH - BATTERY AND BODY GROUND) Disconnect the main body ECU RH connector. Measure the voltage and resistance of the wire harness side connector. Standard voltage Tester Connection Condition Specified Condition BATB (RN-1) - Body ground Always 10 to 14 V Standard resistance Tester Connection Specified Condition GND2 (RD-7) - Body ground Below 1 ohms GND1 (RD-17) - Body ground Below 1 ohms NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
  3. CHECK RESISTANCE OF COMMUNICATION LINE Disconnect the J75 and RJ ECU connectors. Disconnect the J76 ECU connector. Disconnect the P33 ECU connector. Measure the resistance between the specified terminals on the wire harness side connectors. Standard resistance Tester Connection Specified Condition MPX2 (J75-21) - MPD1 (J76-3) Below 1 ohms MPX1 (RJ-21) - MPX1 (P33-27) Below 1 ohms Result Result Proceed to Both are OK A One is OK B Both are NG C B --> REPLACE BODY ECU AND REPAIR OR REPLACE HARNESS OR CONNECTOR C --> REPAIR OR REPLACE HARNESS OR CONNECTOR A --> REPLACE BODY ECU
  1. INSPECT FUSE (FR DOOR LH) Remove the FR DOOR LH fuse from the cowl side J/B LH. Measure the resistance of the fuse. Standard resistance Below 1 ohms NG --> REPLACE FUSE OK: Go to next step
  2. CHECK WIRE HARNESS (POWER WINDOW MASTER SWITCH - BATTERY AND BODY GROUND) Disconnect the M17 switch connector. Turn the engine switch on (IG). Measure the voltage and resistance of the wire harness side connector. Standard voltage Tester Connection Condition Specified Condition CPUB (M17-15) - Body ground Always 10 to 14 V Standard resistance Tester Connection Specified Connection E (M17-12) - Body ground Below 1 ohms NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
  3. CHECK RESISTANCE OF COMMUNICATION LINE Disconnect the M17, Q3 and P33 ECU connectors. Measure the resistance between the specified terminals on the wire harness side connectors. Standard resistance Tester Connection Specified Condition MPX1 (M17-3) - MPX1 (Q3-15) Below 1 ohms MPX2 (M17-2) - MPX2 (P33-28) Below 1 ohms Result Result Proceed to Both are OK A One is OK B Both are NG C B --> REPAIR OR REPLACE HARNESS OR CONNECTOR AND REPLACE POWER WINDOW MASTER SWITCH C --> REPAIR OR REPLACE HARNESS OR CONNECTOR A --> REPLACE POWER WINDOW MASTER SWITCH
  1. INSPECT FUSE (SECURITY) Remove the SECURITY fuse from the cowl side J/B LH. Measure the resistance of the fuse. Standard resistance Below 1 ohms NG --> REPLACE FUSE OK: Go to next step
  2. CHECK WIRE HARNESS (CERTIFICATION ECU - BATTERY AND BODY GROUND) Disconnect the P33 ECU connector. Measure the voltage and resistance of the wire harness side connector. Standard voltage Tester Connection Condition Specified Condition +B1 (P33-1) - Body ground Always 10 to 14 V Standard resistance Tester Connection Specified Condition E (P33-17) - Body ground Below 1 ohms NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
  3. CHECK RESISTANCE OF COMMUNICATION LINE Disconnect the P33, RJ and M17 ECU connectors. Measure the resistance between the specified terminals on the wire harness side connectors. Standard resistance Tester Connection Specified Condition MPX1 (P33-27) - MPX1 (RJ-21) Below 1 ohms MPX2 (P33-28) - MPX2 (M17-2) Below 1 ohms Result Result Proceed to Both are OK A One is OK B Both are NG C B --> REPAIR OR REPLACE HARNESS OR CONNECTOR AND REPLACE CERTIFICATION ECU C --> REPAIR OR REPLACE HARNESS OR CONNECTOR A --> REPLACE CERTIFICATION ECU
  1. INSPECT FUSE (FR DOOR RH, MPX-B) Remove the FR DOOR RH fuse from the cowl side J/B RH. Remove the MPX-B fuse from the engine room R/B No. 1. Measure the resistance of the fuse. Standard resistance Below 1 ohms NG --> REPLACE FUSE OK: Go to next step
  2. CHECK WIRE HARNESS (OUTER MIRROR CONTROL ECU - BATTERY AND BODY GROUND) Disconnect the L10 ECU connector. Measure the voltage and resistance of the wire harness side connector. Standard voltage Tester Connection Condition Specified Condition BDR (L10-6) - Body ground Always 10 to 14 V CPUB (L10-4) - Body ground Always 10 to 14 V Standard resistance Tester Connection Specified Condition GND (L10-1) - Body ground Below 1 ohms NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
  3. CHECK RESISTANCE OF COMMUNICATION LINE Disconnect the L10, P33 and RJ ECU connectors. Measure the resistance between the specified terminals on the wire harness side connectors. Standard resistance Tester Connection Specified Condition MPX1 (L10-8) - MPX1 (P33-27) Below 1 ohms MPX1 (L10-8) - MPX1 (RJ-21) Below 1 ohms Result Result Proceed to Both are OK A One is OK B Both are NG C B --> REPAIR OR REPLACE HARNESS OR CONNECTOR OR REPLACE OUTER MIRROR CONTROL ECU AND REPAIR C --> REPAIR OR REPLACE HARNESS OR CONNECTOR A --> REPLACE OUTER MIRROR CONTROL ECU
  1. INSPECT FUSE (FR DOOR LH) Remove the FR DOOR LH fuse from the cowl side J/B LH. Measure the resistance of the fuse. Standard resistance Below 1 ohms NG --> REPLACE FUSE OK: Go to next step
  2. CHECK HARNESS AND CONNECTOR (OUTER MIRROR CONTROL ECU - BATTERY AND BODY GROUND) Disconnect the M10 ECU connector. Measure the voltage and resistance of the wire harness side connector. Standard voltage Tester Connection Condition Specified Condition BDR (M10-6) - Body ground Always 10 to 14 V Standard resistance Tester Connection Specified Condition GND (M10-1) - Body ground Below 1 ohms NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
  3. CHECK RESISTANCE OF COMMUNICATION LINE Disconnect the M10, J55 and 2F ECU connectors. Measure the resistance between the specified terminals on the wire harness side connectors. Standard resistance Tester Connection Specified Condition MPX1 (M10-8) - MPX2 (J55-24) Below 1 ohms MPX1 (M10-8) - 2F-5 Below 1 ohms Result Result Proceed to Both are OK A One is OK B Both are NG C B --> REPAIR OR REPLACE HARNESS OR CONNECTOR AND REPLACE OUTER MIRROR CONTROL ECU C --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> REPLACE OUTER MIRROR CONTROL ECU
  1. INSPECT FUSE (AM2) Remove the AM2 fuse from the cowl side J/B RH. Measure the resistance of the fuse. Standard resistance Below 1 ohms NG --> REPLACE FUSE OK: Go to next step
  2. CHECK WIRE HARNESS (POWER SOURCE CONTROL ECU - BATTERY AND BODY GROUND) Disconnect the J55 ECU connector. Measure the resistance and voltage of the wire harness side connector. Standard voltage Tester Connection Condition Specified Condition J55-33 (AM1) - Body ground Always 10 to 14 V J55-12 (AM2) - Body ground Always 10 to 14 V Standard resistance Tester Connection Specified Condition J55-6 (GND2) - Body ground Below 1 ohms NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
  3. CHECK RESISTANCE OF COMMUNICATION LINE Disconnect the J55, J26 and 2F ECU connectors. Measure the resistance between the specified terminals on the wire harness side connectors. Standard resistance Tester Connection Specified Condition MPX1 (J55-7) - MPX2 (J26-7) Below 1 ohms MPX2 (J55-24) - 2F-5 Below 1 ohms Result Result Proceed to Both are OK A One is OK B Both are NG C B --> REPLACE POWER SOURCE CONTROL ECU AND REPAIR OR REPLACE HARNESS OR CONNECTOR C --> REPAIR OR REPLACE HARNESS OR CONNECTOR A --> REPLACE POWER SOURCE CONTROL ECU
  1. INSPECT FUSE (TI & TE, MPX-B) Remove the TI & TE fuse from the cowl side J/B RH. Remove the MPX-B fuse from the engine room R/B No. 1. Measure the resistance of the fuse. Standard resistance Below 1 ohms NG --> REPLACE FUSE OK: Go to next step
  2. CHECK WIRE HARNESS (TILT AND TELESCOPIC ECU - BATTERY AND BODY GROUND) Disconnect the J28 ECU connector. Measure the resistance and voltage of the wire harness side connector. Standard voltage Tester Connection Condition Specified Condition +B (J28-2) - Body ground Always 10 to 14 V ECUB (J28-9) - Body ground Always 10 to 14 V Standard resistance Tester Connection Specified Condition GND (J28-11) - Body ground Below 1 ohms NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
  3. CHECK RESISTANCE OF COMMUNICATION LINE Disconnect the J28, RA and RJ ECU connectors. Measure the resistance between the specified terminals on the wire harness side connectors. Standard resistance Tester Connection Specified Condition MPX1 (J28-5) - MPX1 (P33-27) Below 1 ohms MPX1 (J28-5) - RA-20 Below 1 ohms Result Result Proceed to Both are OK A One is OK B Both are NG C B --> REPAIR OR REPLACE HARNESS OR CONNECTOR AND REPLACE TILT AND TELESCOPIC ECU C --> REPAIR OR REPLACE HARNESS OR CONNECTOR A --> REPLACE TILT AND TELESCOPIC ECU
  1. CHECK DIAGNOSTIC TROUBLE CODE (A ECU) Disconnect the A ECU connector and check for DTCs B1214 and B1215. OK Neither DTC B1214 nor DTC B1215 is output. NOTE: Reconnect the connector before starting the next check. HINT: The A ECU in the door system bus represents the main body ECU RH. If the result is as specified, the disconnected A ECU (main body ECU RH) is malfunctioning. OK --> REPLACE A ECU NG: Go to next step
  2. CHECK DIAGNOSTIC TROUBLE CODE (B ECU) Disconnect the A ECU and B ECU connectors and check for DTCs B1214 and B1215. OK Neither DTC B1214 nor DTC B1215 is output. NOTE: Disconnect the connectors one by one. Reconnect the connectors before starting the next check. HINT: Remove the B ECUs in the following order: Tilt and telescopic ECU Power window master switch Certification ECU Power source control ECU Position control ECU and switch (Front LH seat) Main body ECU LH Outer mirror control ECU (RH) Outer mirror control ECU (LH) Front controller Overhead J/B Rain sensor Sliding roof control ECU If the result is as specified, the disconnected B ECU (one of the ECUs from the above list) or the wire harness between the A ECU and B ECU is malfunctioning. After the DTC is cleared, proceed to the next step. NG --> See step 4 OK: Go to next step
  3. CHECK WIRE HARNESS BETWEEN A ECU AND B ECU Disconnect the B ECU connector and check for DTCs B1214 and B1215. OK Neither DTC B1214 nor DTC B1215 is output. NOTE: Reconnect the connector before starting the next check. HINT: If the result is as specified, the wire harness between the A ECU and B ECU is functioning normally but the disconnected B ECU is malfunctioning. NG --> REPAIR OR REPLACE WIRE HARNESS BETWEEN A ECU AND B ECU OK --> REPLACE B ECU
  4. CHECK DIAGNOSTIC TROUBLE CODE (C ECU) Disconnect the B ECU and C ECU connectors and check for DTCs B1214 and B1215. OK Neither DTC B1214 nor DTC B1215 is output. NOTE: Disconnect the connectors one by one. Reconnect the connectors before starting the next check. HINT: The C ECU in the door system bus represents the windshield wiper switch. If the result is as specified, the disconnected C ECU (windshield wiper switch) or the wire harness between the B ECU and C ECU is malfunctioning. NG --> See step 6 OK: Go to next step
  5. CHECK WIRE HARNESS BETWEEN B ECU AND C ECU Disconnect the C ECU connector and check for DTCs B1214 and B1215. OK Neither DTC B1214 nor DTC B1215 is output. NOTE: Reconnect the connector before starting the next check. HINT: If the result is as specified, the wire harness between the B ECU and C ECU is functioning normally but the disconnected C ECU is malfunctioning. NG --> REPAIR OR REPLACE WIRE HARNESS BETWEEN B ECU AND C ECU OK --> REPLACE C ECU
  6. CHECK WIRE HARNESS BETWEEN NETWORK GATEWAY ECU AND A ECU OR C ECU Check for a short circuit in B+ or body ground. Disconnect the A ECU, C ECU and multiplex network gateway ECU connectors. Measure the voltage and resistance of the wire harness side connectors. Standard voltage Tester Connection Specified Condition A ECU connector/multiplex network gateway ECU connector - Body ground Below 1 V C ECU connector/multiplex network gateway ECU connector - Body ground Below 1 V Standard resistance Tester Connection Specified Condition A ECU connector/multiplex network gateway ECU connector - Body ground 10 kohms or higher C ECU connector/multiplex network gateway ECU connector - Body ground 10 kohms or higher HINT: The A ECU in the door system bus represents the main body ECU RH. The C ECU in the door system bus represents the windshield wiper switch. NG --> REPAIR OR REPLACE WIRE HARNESS BETWEEN NETWORK GATEWAY ECU AND A ECU OR C ECU OK --> REPLACE MULTIPLEX NETWORK GATEWAY ECU
  1. INSPECT FUSE (ECU-IG LH) Remove the ECU-IG LH fuse from the cowl side J/B LH. Measure the resistance of the fuse. Standard resistance Below 1 ohms NG --> REPLACE FUSE OK: Go to next step
  2. CHECK WIRE HARNESS (TIRE PRESSURE MONITOR ECU - BATTERY AND BODY GROUND) Disconnect the J49 ECU connector. Measure the voltage and resistance of the wire harness side connector Standard voltage Tester Connection Condition Specified Condition IG (J49-1) - Body ground Engine switch on (IG) 10 to 14 V Standard resistance Tester Connection Specified Condition GND (J49-6) - Body ground Below 1 ohms NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
  3. CHECK RESISTANCE COMMUNICATION LINE Disconnect the J49, J34 and J76 ECU connectors. Measure the resistance between the specified terminals on the wire harness side connectors. Standard resistance Tester Connection Specified Condition MPX1 (J49-3) - MPX- (J34-18) Below 1 ohms MPX2 (J49-2) - MPI1 (J76-4) Below 1 ohms Result Result Proceed to Both are OK A One is OK B Both are NG C B --> REPAIR OR REPLACE HARNESS OR CONNECTOR C --> REPLACE TIRE PRESSURE MONITOR ECU AND REPAIR OR REPLACE HARNESS OR CONNECTOR A --> REPLACE TIRE PRESSURE MONITOR ECU
  1. CHECK OPERATION Check for AVC-LAN communication DTCs. OK AVC-LAN communication DTCs are not output, and there are no symptoms specified in the problem symptoms table. NG --> GO TO "DIAGNOSTICS TROUBLE CODE TABLE" OF AUDIO SYSTEM OR NAVIGATION SYSTEM OK --> REPLACE GATEWAY ECU
  1. CHECK FUSE (A/C) Remove the A/C fuse from the cowl side J/B LH. Measure the resistance of the fuse. Standard resistance Below 1 ohms NG --> REPLACE FUSE OK: Go to next step
  2. CHECK WIRE HARNESS (AIR CONDITIONING AMPLIFIER - BATTERY AND BODY GROUND) Disconnect the J58 ECU connector. Measure the voltage and resistance of the wire harness side connector. Standard voltage Tester Connection Condition Specified Condition B (J58-1) - Body ground Always 10 to 14 V Standard resistance Tester Connection Specified Condition GND (J58-20) - Body ground Below 1 ohms TEXT IN ILLUSTRATION *1 Front view of wire harness connector (to Air Conditioning Amplifier Assembly) NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
  3. CHECK RESISTANCE OF COMMUNICATION LINE Disconnect the J58, J34 and J76 ECU connectors. Measure the resistance of the wire harness side connector. Standard resistance Tester Connection Specified Condition MPX- (J58-31) - MPX+ (J34-6) Below 1 ohms MPX+ (J58-30) - MPI2 (J76-13) Below 1 ohms Result Result Proceed to Both are OK A One is OK B Both are NG C TEXT IN ILLUSTRATION *1 Front view of wire harness connector (to Air Conditioning Amplifier Assembly) *2 Front view of wire harness connector (to Combination Meter Assembly) *3 Front view of wire harness connector (to Gateway ECU) B --> REPLACE AIR CONDITIONING AMPLIFIER AND REPAIR OR REPLACE HARNESS OR CONNECTOR C --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY
  1. CHECK DIAGNOSTIC TROUBLE CODE (A ECU) Disconnect the A ECU connector and check for DTCs B1266 and B1267. OK Neither DTC B1266 nor DTC B1267 is output. NOTE: Reconnect the connector before starting the next check. HINT: The A ECU in the instrument panel system bus represents the air conditioning amplifier. If the result is as specified, the disconnected A ECU (air conditioning amplifier) is malfunctioning. OK --> REPLACE A ECU NG: Go to next step
  2. CHECK DIAGNOSTIC TROUBLE CODE (B ECU) Disconnect the A ECU and B ECU connectors and check for DTCs B1266 and B1267. OK Neither DTC B1266 nor DTC B1267 is output. NOTE: Disconnect the connectors one by one. Reconnect the connectors before starting the next check. HINT: Remove the B ECUs in the following order: Clearance warning ECU Combination meter ECU If the result is as specified, the disconnected B ECU (one of the ECUs from the above list) or the wire harness between the A ECU and B ECU is malfunctioning. After the DTC is cleared, proceed to the next step. NG --> See step 4 OK: Go to next step
  3. CHECK WIRE HARNESS BETWEEN A ECU AND B ECU Disconnect the B ECU connector and check for DTCs B1266 and B1267. OK Neither DTC B1266 nor DTC B1267 is output. NOTE: Reconnect the connector before starting the next check. HINT: If the result is as specified, the wire harness between the A ECU and B ECU is functioning normally but the disconnected B ECU is malfunctioning. NG --> REPAIR OR REPLACE WIRE HARNESS BETWEEN A ECU AND B ECU OK --> REPLACE B ECU
  4. CHECK DIAGNOSTIC TROUBLE CODE (C ECU) Disconnect the B ECU and C ECU connectors and check for DTCs B1266 and B1267. OK Neither DTC B1266 nor DTC B1267 is output. NOTE: Disconnect the connectors one by one. Reconnect the connectors before starting the next check. HINT: The C ECU in the instrument panel system bus represents the tire pressure warning ECU. If the result is as specified, the disconnected C ECU (tire pressure warning ECU) or the wire harness between the B ECU and C ECU is malfunctioning. NG --> See step 6 OK: Go to next step
  5. CHECK WIRE HARNESS BETWEEN B ECU AND C ECU Disconnect the C ECU connector and check for DTCs B1266 and B1267. OK Neither DTC B1266 nor DTC B1267 is output. NOTE: Reconnect the connector before starting the next check. HINT: If the result is as specified, the wire harness between the B ECU and C ECU is functioning normally but the disconnected C ECU is malfunctioning. NG --> REPAIR OR REPLACE WIRE HARNESS BETWEEN B ECU AND C ECU OK --> REPLACE C ECU
  6. CHECK WIRE HARNESS BETWEEN GATEWAY ECU AND A ECU OR C ECU Check for a short-circuit in B+ or body ground. Disconnect the A ECU, C ECU and multiplex network gateway ECU connectors. Measure the resistance and voltage of the wire harness side connectors. Standard voltage Tester Connection Specified Condition A ECU connector/multiplex network gateway ECU connector - Body ground Below 1 V C ECU connector/multiplex network gateway ECU connector - Body ground Below 1 V Standard resistance Tester Connection Specified Condition A ECU connector/multiplex network gateway ECU connector - Body ground 10 kohms or higher C ECU connector/multiplex network gateway ECU connector - Body ground 10 kohms or higher HINT: The A ECU in the instrument panel system bus represents the air conditioning amplifier. The C ECU in the instrument panel system bus represents the tire pressure monitor ECU. NG --> REPAIR OR REPLACE WIRE HARNESS BETWEEN GATEWAY ECU AND A ECU OR C ECU OK --> REPLACE MULTIPLEX NETWORK GATEWAY ECU
  1. INSPECT FUSE (DOME, MPX-B) Remove the DOME and MPX-B fuses from the engine room J/B No. 1. Measure the resistance of the fuse. Standard resistance Below 1 ohms NG --> REPLACE FUSE OK: Go to next step
  2. CHECK WIRE HARNESS (COMBINATION METER ECU - BATTERY AND BODY GROUND) Disconnect the J34 ECU connector. Measure the voltage and resistance of the wire harness side connector. Standard voltage Tester Connection Condition Specified Condition B (J34-23) - Body ground Always 10 to 14 V B (J34-24) - Body ground Always 10 to 14 V Standard resistance Tester Connection Specified Condition E2 (J34-1) - Body ground Below 1 ohms ES (J34-13) - Body ground Below 1 ohms TEXT IN ILLUSTRATION *1 Front view of wire harness connector (to Combination Meter Assembly) NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
  3. CHECK RESISTANCE OF COMMUNICATION LINE Disconnect the J34, J49, J76 and J58 ECU connectors. Measure the resistance between the specified terminals on the wire harness side connectors. Standard resistance Tester Connection Specified Condition MPX- (J34-18) - MPX1 (J49-3)*1 Below 1 ohms MPX- (J34-18) - MPI1 (J76-4)*2 Below 1 ohms MPX+ (J34-6) - MPX- (J58-31) Below 1 ohms *1: w/ Tire Pressure Warning System *2: w/o Tire Pressure Warning System Result Result Proceed to Both are OK A One is OK B Both are NG C TEXT IN ILLUSTRATION *1 Front view of wire harness connector (to Combination Meter ECU) *2 Front view of wire harness connector (to Tire Pressure Monitor ECU) *3 Front view of wire harness connector (to Gateway ECU) *4 Front view of wire harness connector (to Air Conditioning Amplifier) B --> REPLACE COMBINATION METER ECU AND REPAIR OR REPLACE HARNESS OR CONNECTOR C --> REPAIR OR REPLACE HARNESS OR CONNECTOR A --> REPLACE COMBINATION METER ECU
  1. INSPECT FUSE (FR P/SEAT LH, MPX-B) Remove the FR P/SEAT LH fuse from the cowl side J/B LH. Remove the MPX-B fuse from the engine room J/B No. 1. Measure the resistance of the fuse. Standard resistance Below 1 ohms NG --> REPLACE FUSE OK: Go to next step
  2. CHECK WIRE HARNESS (POSITION CONTROL ECU AND SWITCH - BATTERY AND BODY GROUND) Disconnect the U7 and U6 ECU connector. Measure the voltage and resistance of the wire harness side connector Standard voltage Tester Connection Condition Specified Condition SYSB (U7-8) - Body ground Always 10 to 14 V +B (U6-5) - Body ground Always 10 to 14 V Standard resistance Tester Connection Specified Condition GND (U6-1) - Body ground Below 1 ohms NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
  3. CHECK RESISTANCE OF COMMUNICATION LINE Disconnect the 2F and J55 ECU connectors. Measure the resistance between the specified terminals on the wire harness side connectors. Standard resistance Tester Connection Specified Condition MPX1 (U7-1) - 2F-5 Below 1 ohms MPX1 (U7-1) - MPX2 (J55-24) Below 1 ohms Result Result Proceed to Both are OK A One is OK B Both are NG C B --> REPAIR OR REPLACE HARNESS OR CONNECTOR AND REPLACE POSITION CONTROL ECU C --> REPAIR OR REPLACE HARNESS OR CONNECTOR A --> REPLACE POSITION CONTROL ECU AND SWITCH
  1. INSPECT FUSE (S/ROOF) Remove the S/ROOF fuse from the cowl side J/B LH. Measure the resistance of the fuse. Standard resistance Below 1 ohms NG --> REPLACE FUSE OK: Go to next step
  2. CHECK WIRE HARNESS (SLIDING ROOF CONTROL ECU - BATTERY AND BODY GROUND) Disconnect the R6 ECU connector. Measure the voltage and resistance of the wire harness side connector. Standard voltage Tester Connection Condition Specified Condition B (R6-5) - Body ground Always 10 to 14 V Standard resistance Tester Connection Specified Condition E (R6-7) - Body ground Below 1 ohms NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
  3. CHECK RESISTANCE OF COMMUNICATION LINE Disconnect the R6 and R5 connectors. Measure the resistance between the specified terminals on the wire harness side connectors. Standard resistance Tester Connection Specified Condition MPX1 (R6-10) - MPX2 (R5-38) Below 1 ohms NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
  4. CHECK RESISTANCE COMMUNICATION LINE Disconnect the R5, J55 and 2F ECU connectors. Measure the resistance between the specified terminals on the wire harness side connectors. Standard resistance Tester Connection Specified Condition MPX (R5-36) - MPX2 (J55-24) Below 1 ohms MPX (R5-36) - 2F-5 Below 1 ohms Result Result Proceed to Both are OK A One is OK B Both are NG C B --> REPAIR OR REPLACE HARNESS OR CONNECTOR AND REPLACE SLIDING ROOF ECU C --> REPAIR OR REPLACE HARNESS OR CONNECTOR A --> REPLACE SLIDING ROOF CONTROL ECU
  1. INSPECT FUSE (ECU-IG RH, MPX-B) Remove the ECU-IG RH fuse from the cowl side J/B RH. Remove the MPX-B fuse from the engine room J/B No. 1. Standard resistance Below 1 ohms NG --> REPLACE FUSE OK: Go to next step
  2. CHECK WIRE HARNESS (COMBINATION SWITCH ASSEMBLY - BATTERY AND BODY GROUND) Disconnect the J26 ECU connector. Measure the voltage and resistance of the wire harness side connector. Standard voltage Tester Connection Condition Specified Condition B (J26-1) - Body ground Always 10 to 14 V IG (J26-2) - Body ground Engine switch on (IG) 10 to 14 V Standard resistance Tester Connection Specified Condition E (J26-5) - Body ground Below 1 ohms NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
  3. CHECK RESISTANCE OF COMMUNICATION LINE Disconnect the J26, J76 and J55 ECU connectors. Measure the resistance between the specified terminals on the wire harness side connectors. Standard resistance Tester Connection Specified Condition MPX1 (J26-6) - MPD2 (J76-12) Below 1 ohms MPX2 (J26-7) - MPX1 (J55-7) Below 1 ohms Result Result Proceed to Both are OK A One is OK B Both are NG C B --> REPAIR OR REPLACE HARNESS OR CONNECTOR AND REPLACE COMBINATION SWITCH ASSEMBLY C --> REPAIR OR REPLACE HARNESS OR CONNECTOR A --> REPLACE COMBINATION SWITCH ASSEMBLY
  1. INSPECT FUSE (ECU-IG LH) Remove the ECU-IG LH fuse from the cowl side J/B LH. Measure the resistance of the fuse. Standard resistance Below 1 ohms NG --> REPLACE FUSE OK: Go to next step
  2. CHECK WIRE HARNESS (OVERHEAD J/B - BATTERY AND BODY GROUND) Disconnect the R5 connector. Measure the voltage and resistance of the wire harness side connector. Standard voltage Tester Connection Condition Specified Condition IG (R5-21) - Body ground Engine switch on (IG) 10 to 14 V Standard resistance Tester Connection Specified Condition GND1 (R5-39) - Body ground Below 1 ohms NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
  3. CHECK WIRE HARNESS (RAIN SENSOR - BATTERY AND BODY GROUND) Disconnect the R7 connector. Measure the voltage and resistance of the wire harness side connector. Standard voltage Tester Connection Condition Specified Condition SIG (R7-1) - Body ground Engine switch on (IG) 10 to 14 V Standard resistance Tester Connection Specified Condition ES (R7-3) - Body ground Below 1 ohms NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
  4. CHECK RESISTANCE OF COMMUNICATION LINE Disconnect the R7 and R5 ECU connectors. Measure the resistance between the specified terminals on the wire harness side connectors. Standard resistance Tester Connection Specified Condition MPX (R7-2) - MPX1 (R5-37) Below 1 ohms Result Result Proceed to Both are OK A One is OK B Both are NG C B --> REPAIR OR REPLACE HARNESS OR CONNECTOR OR REPLACE RAIN SENSOR C --> REPAIR OR REPLACE HARNESS OR CONNECTOR A --> REPLACE RAIN SENSOR
  1. INSPECT FUSE (MPX-B) Remove the MPX-B from the engine room J/B No. 1. Measure the resistance of the fuse. Standard resistance Below 1 ohms NG --> REPLACE FUSE OK: Go to next step
  2. CHECK WIRE HARNESS (MAIN BODY ECU LH - BATTERY AND BODY GROUND) Disconnect the LD ECU connector. Measure the voltage and resistance of the wire harness side connector. Standard voltage Tester Connection Condition Specified Condition MPXB (LD-18) - Body ground Always 10 to 14 V Standard resistance Tester Connection Specified Condition GND (LD-3) - Body ground Below 1 ohms NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
  3. CHECK RESISTANCE OF COMMUNICATION LINE Disconnect the Q3, A30, M17 and 2F ECU connectors. Measure the resistance between the specified terminals on the wire harness side connectors. Standard resistance Tester Connection Specified Condition MPX1 (Q3-15) - MPX1 (M17-3) Below 1 ohms MPX2 (A30-17) - 2F-6 Below 1 ohms Result Result Proceed to Both are OK A One is OK B Both are NG C B --> REPAIR OR REPLACE HARNESS OR CONNECTOR AND REPLACE MAIN BODY ECU LH C --> REPAIR OR REPLACE HARNESS OR CONNECTOR A --> REPLACE MAIN BODY ECU LH
  1. INSPECT FUSE (MPX-B) Remove the MPX-B fuse from the engine room J/B No. 1. Measure the resistance of the fuse. Standard resistance Below 1 ohms NG --> REPLACE FUSE OK: Go to next step
  2. CHECK WIRE HARNESS (FRONT CONTROLLER - BATTERY AND BODY GROUND) Disconnect the 2E and 2F ECU connectors. Measure the voltage and resistance of the wire harness side connectors. Standard voltage Tester Connection Condition Specified Condition 2E-4 - Body ground Always 10 to 14 V Standard resistance Tester Connection Specified Condition 2F-1 - Body ground Below 1 ohms NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
  3. CHECK RESISTANCE OF COMMUNICATION LINE Disconnect the 2F, A30 and J55 ECU connectors. Measure the resistance between the specified terminals on the wire harness side connectors. Standard resistance Tester Connection Specified Condition 2F-6 - MPX2 (A30-17) Below 1 ohms 2F-5 - MPX2 (J55-24) Below 1 ohms Result Result Proceed to Both are OK A One is OK B Both are NG C B --> REPAIR OR REPLACE HARNESS OR CONNECTOR AND REPLACE FRONT CONTROLLER C --> REPAIR OR REPLACE HARNESS OR CONNECTOR A --> REPLACE FRONT CONTROLLER
  1. INSPECT FUSE (LH-IG) Remove the LH-IG fuse from the cowl side J/B LH. Measure the resistance of the fuse. Standard resistance Below 1 ohms NG --> REPLACE FUSE OK: Go to next step
  2. CHECK WIRE HARNESS (CLEARANCE WARNING ECU - BATTERY AND BODY GROUND) Disconnect the Q37 ECU connector. Measure the voltage and resistance of the wire harness side connector. Standard voltage Tester Connection Condition Specified Condition IG (Q37-8) - Body ground Engine switch on (IG) 10 to 14 V Standard resistance Tester Connection Specified Condition E (Q37-27) - Body ground Below 1 ohms TEXT IN ILLUSTRATION *1 Front view of wire harness connector (to Clearance Warning ECU Assembly) NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
  3. CHECK RESISTANCE OF COMMUNICATION LINE Disconnect the Q37, J58 and J34 ECU connectors. Measure the resistance between the specified terminals on the wire harness side connectors. Standard resistance Tester Connection Specified Condition M+ (Q37-26) - MPX- (J58-31) Below 1 ohms M+ (Q37-26) - MPX+ (J34-6) Below 1 ohms Result Result Proceed to Both are OK A One is OK B Both are NG C TEXT IN ILLUSTRATION *1 Front view of wire harness connector (to Clearance Warning ECU Assembly) *2 Front view of wire harness connector (to Air Conditioning Amplifier Assembly) *3 Front view of wire harness connector (to Combination Meter Assembly) B --> REPAIR OR REPLACE HARNESS OR CONNECTOR AND REPLACE CLEARANCE WARNING ECU C --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> REPLACE CLEARANCE WARNING ECU

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