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Diagnostic Item 5: Communication with no ECUs is possible (GW-CAN-C). <Vehicles with Blind Spot Warning [BSW] (with Lane Change Assist) system>
 
 
cautionWhen servicing a CAN bus line, ground yourself by touching a metal object such as an unpainted water pipe. If you fail to do, a component connected to the CAN bus line may be broken.
 
 
TROUBLESHOOTING HINTS
  • Malfunction in GW-CAN-C (short to ground or power supply, wire short to one another)
  • Malfunction in the ECUs which are interconnected via GW-CAN-C (internal error)
  • Malfunction (open circuit) of wiring harness, connector(s) between the gateway-ECU and BSW-ECU (master)
 
 
DIAGNOSIS
Required Special Tools:
  • MB991223: Harness Set
  • MB992006: Extra Fine Probe
STEP 1. Check the GW-CAN-C for short to power supply. Voltage measurement at gateway-ECU connector by backprobing.
cautionA digital multimeter should be used. For details refer to .
cautionThe test wiring harness should be used. For details refer to .
(1) Connect the negative 12V starter battery terminal, and turn on the power supply mode of the electric motor switch.
(2) Voltage between the gateway-ECU connector terminal No.6 (CAN_H) and body ground by backprobing
OK: Less than 4.0 V
(3) Voltage between the gateway-ECU connector terminal No.5 (CAN_L) and body ground by backprobing
OK: Less than 4.0 V
(4) Disconnect the negative 12V starter battery terminal.
Is the check result normal?
Go to Step 2.
Perform diagnostic item 6 "Diagnose shorts in the power supply to GW-CAN-C". Refer to .
 
STEP 2. Check the GW-CAN-C for short to ground. Resistance measurement at gateway-ECU connector by backprobing.
cautionA digital multimeter should be used. For details refer to .
cautionThe test wiring harness should be used. For details refer to .
(1) Turn off the power supply mode of the electric motor switch.
(2)
cautionWhen measuring the resistance, disconnect the negative 12V starter battery terminal. For details refer to .
Ensure that the negative 12V starter battery terminal is disconnected.
(3) Resistance between the gateway-ECU connector terminal No.6 (CAN_H) and body ground by backprobing
OK: 1 kΩ or more
(4) Resistance between the gateway-ECU connector terminal No.5 (CAN_L) and body ground by backprobing
OK: 1 kΩ or more
Is the check result normal?
Go to Step 3.
Perform diagnostic item 7 "Diagnose shorts in the ground to GW-CAN-C". Refer to .
 
STEP 3. Check the GW-CAN-C for short to each other. Resistance measurement at gateway-ECU connector by backprobing.
cautionA digital multimeter should be used. For details refer to .
cautionThe test wiring harness should be used. For details refer to .
(1) Turn off the power supply mode of the electric motor switch.
(2)
cautionWhen measuring the resistance, disconnect the negative 12V starter battery terminal. For details refer to .
Ensure that the negative 12V starter battery terminal is disconnected.
(3) Resistance between the gateway-ECU connector terminal Nos.6 and 5 by backprobing
OK: 60 ± 10 ohms
Is the check result normal?
: Power supply to the BSW-ECU (master) may be suspected. Diagnose the BSW-ECU. Refer to GROUP 54A - Troubleshooting .
: Perform diagnostic Item 8 "Diagnose shorts between CAN_H and L lines (GW-CAN-C)". Refer to .
: Perform diagnostic Item 32 "Diagnose when the scan tool cannot receive the data sent by BSW-ECU". Refer to .