Multiplex Communication: Diagnosis Toyota 4Runner IV рестайлинг

HOW TO PROCEED WITH TROUBLESHOOTING

HINT

1. Use this procedure to troubleshoot the multiplex communication system.
2. The intelligent tester should be used in step 2 .

1. VEHICLE BROUGHT TO WORKSHOP
2. CHECK FOR DTC Check for DTCs and note any codes that are output. Delete the DTC. Recheck for DTCs. Try to prompt the DTC by simulating the original activity that the DTC suggests. Result RESULT REFERENCE Result Proceed to DTC does not reoccur A DTC reoccurs B B: GO TO «DTC CHART»(ref-280588-S06546234292008022200000) A: Go to next step.
3. OVERALL ANALYSIS AND TROUBLESHOOTING Terminals of ECU (See «TERMINALS OF ECU»(ref-280588-S08944324432008022200000) ).
4. ADJUST, REPAIR OR REPLACE
5. CONFIRMATION TEST NEXT: END

Scheme 60

Scheme 61

Scheme 62

1. CHECK DRIVER SIDE JUNCTION BLOCK ASSEMBLY (BODY ECU) Disconnect the 1B, 1E, 1F, 1H and 1L J/B connectors. Measure the voltage and resistance of the wire harness side connector. DRIVER SIDE JUNCTION BLOCK ASSEMBLY (BODY ECU) Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition BECU (1F-12) - Body ground W-R - Body ground Power source (+B) Always 10 to 14 V BECU (1B-4) - Body ground W-R - Body ground Power source (+B) Always 10 to 14 V BECU (1L-4) - Body ground W-R - Body ground Power source (+B) Always 10 to 14 V BDR1 (1E-9) - Body ground G-W - Body ground Power source (+B) Always 10 to 14 V GND1 (1H-2)-Body ground W-B - Body ground Ground for main power supply Always Below 1 ohms GND2 (1H-2) - Body ground W-B - Body ground Ground for main power supply Always Below 1 ohms If the result is not as specified, there may be a malfunction on the wire harness side.
2. CHECK THEFT WARNING ECU ASSEMBLY (THEFT DETERRENT ECU) Disconnect the T5 connector. Measure the voltage and resistance of the wire harness side connectors. THEFT WARNING ECU ASSEMBLY (THEFT DETERRENT ECU) Symbols (Terminals No.) Wiring Color Terminal Description Condition Specified Condition +B1 (T5-2) - Body ground W-R - Body ground Power source (+B) Always 10 to 14 V +B2 (T5-3) - Body ground W-L - Body ground Power source (+B) Always 10 to 14 V E (T5-29) - Body ground W-B - Body ground Ground for main power supply Always Below 1 ohms If the result is not as specified, there may be a malfunction on the wire harness side.
3. CHECK MULTIPLEX NETWORK DOOR ECU BACK (BACK DOOR ECU) Disconnect the B8 connector. Measure the voltage and resistance of the wire harness side connector. MULTIPLEX NETWORK DOOR ECU BACK (BACK DOOR ECU) Symbols (Terminals No.) Wiring Color Terminal Description Condition Specified Condition BDR (B8-4)- Body ground L - Body ground Power source (+B) Always 10 to 14 V BECU (B8-5) - Body ground L-R - Body ground Power source (+B) Always 10 to 14 V GND (B8-3) - Body ground W-B - Body ground Ground for main power supply Always Below 1 ohms If the result is not as specified, there may be a malfunction on the wire harness side.

Scheme 63

1. DESCRIPTION The network gateway ECU controls the functions of the multiplex communication system on the vehicle. Data of the multiplex communication system and the Diagnostic Trouble Codes (DTC) can be read through the Data Link Connector 3 (DLC3) of the vehicle.
2. CHECK DLC3 The vehicle's ECU uses the ISO 1565-4 for communication protocol. The terminal arrangement of the DLC3 complies with SAEJ1962 and matches the ISO 15765-4 format. DLC3 Symbols (Terminal No.) Terminal Description Condition Specified Condition SIL (7) - SG (5) Bus "+" line During transmission Pulse generation CG (4) - Body ground Chassis ground Always Below 1 ohms SG (5) - Body ground Signal ground Always Below 1 ohms BAT (16) - Body ground Battery positive Always 11 to 14 V If the result is not as specified, the DLC3 may have a malfunction. Repair or replace the harness and connector.
3. MULTIPLEX COMMUNICATION SYSTEM (BEAN) The BEAN communication line consists of 2 systems: One is a system with a loop-shaped line that the back door ECU is united with the body ECU present in the center of the line. Another is a system that the body ECU and the theft deterrent ECU are connected alone. Since the line for the back door ECU is loop-shaped, the communication can be maintained by the line that is not open even if part of the line become open for some reason. In the case that there is a short-circuit (bus-down) in the line, however, all the BEAN communication becomes impossible in the system and some DTCs are output. HINT: When bus-down occurs, communication from the related ECU stops. Therefore, DTC cannot be output, so perform a DTC (SAE code) inspection using the intelligent tester. The theft deterrent ECU and the back door ECU have a single communication line. Therefore, if the line has a short-circuit (bus-down), the BEAN communication will be impossible and DTCs will not be output, either.
4. COMMUNICATION FUNCTION INSPECTION Inspect the battery voltage. Standard voltage: 10 to 14 V Inspect the diagnosis monitor code output. Check a diagnosis code for the body ECU by connecting the intelligent tester to the DLC3 and turning the ignition switch ON. When the display shows diagnostic codes of the ECU unconnected and the communication bus defective, perform the inspection depending on the troubleshooting. HINT: When other diagnostic code is output, refer to the diagnostic code table and check the applicable information.

Scheme 64

1. CHECK DTC Connect the intelligent tester to the DLC3. Turn the ignition switch on. Enter the following menus: DIAGNOSIS/OBD/ MOBD/BODY/DTC INFO. Check the DTCs on the tester screen. HINT: Refer to the intelligent tester operator's manual for further details.
2. CLEAR DTC Connect the intelligent tester to the DLC3. Turn the ignition switch on. Erase the DTCs by following the prompts on the tester screen. Enter the following menus: DIAGNOSIS/OBD/ MOBD/BODY/DTC INFO. HINT: Refer to the intelligent tester operator's manual for further details.

DIAGNOSTIC TROUBLE CODE CHART

If malfunction code is displayed during DTC check, check the circuit corresponding to the code in the table below. Proceed to the page given for the circuit.

MULTIPLEX COMMUNICATION SYSTEM

MULTIPLEX COMMUNICATION DIAGNOSTIC TROUBLE CODE CHART