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Diagnostic Item 6: Diagnose shorts in the power supply to 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.
 
 
TROUBLE JUDGMENT CONDITIONS
The scan tool (M.U.T.-III) judges the trouble when it is impossible to receive the periodically sent data and the voltage of CAN_H or CAN_L line is more than 4.0 V.
 
 
TROUBLESHOOTING HINTS
  • Malfunction of the wiring harness
  • Malfunction of the gateway-ECU
  • Malfunction of the BSW-ECU (master
 
 
DIAGNOSIS
STEP 1. Check the GW-CAN-C. Voltage measurement at gateway-ECU connector.
cautionA digital multimeter should be used. For details refer to .
cautionThe test wiring harness should be used. For details refer to .
(1) Disconnect the gateway-ECU connector and BSW-ECU (master) connector, and measure at the wiring harness side.
(2) Connect the negative battery terminal, and turn the ignition switch to the ON position.
(3) Voltage between the gateway-ECU connector terminal No.6 (CAN_H) and body ground.
OK: 4.0 V or less
(4) Voltage between the gateway-ECU connector terminal No.5 (CAN_L) and body ground.
OK: 4.0 V or less
(5) Disconnect the negative battery terminal.
Is the check result normal?
<4.0 V or less> Go to Step 2.
<More than 4.0 V> Repair intermediate connectors C-25 and G-36, or the wiring harness between the gateway-ECU connector and the BSW-ECU (master) connector.
 
STEP 2. Check the GW-CAN-C. Voltage measurement at BSW-ECU (master) connector.
cautionA digital multimeter should be used. For details refer to .
cautionThe test wiring harness should be used. For details refer to .
(1) Disconnect the BSW-ECU (master) connector, and measure at the wiring harness side.
(2) Connect the negative battery terminal, and turn the ignition switch to the ON position.
(3) Voltage between the BSW-ECU (master) connector terminal No.4 (CAN_H) and body ground.
OK: 4.5 V or less
(4) Voltage between the BSW-ECU (master) connector terminal No.9 (CAN_L) and body ground.
OK: 4.0 V or less
(5) Disconnect the negative battery terminal.
Is the check result normal?
<4.5 V or less (CAN_H) and 4.0V or less (CAN_L)> Go to Step 3.
<More than 4.5 V (CAN_H) or more than 4.0 V (CAN_L)> Check the gateway-ECU connector, and repair if necessary. If the gateway-ECU connector is in good condition, replace the gateway-ECU.
 
STEP 3. Check the GW-CAN-C. Voltage measurement at gateway-ECU connector.
cautionA digital multimeter should be used. For details refer to .
cautionThe test wiring harness should be used. For details refer to .
(1) Disconnect the gateway-ECU connector, and measure at the wiring harness side.
(2) Connect the negative battery terminal, and turn the ignition switch to the ON position.
(3) Voltage between the gateway-ECU connector terminal No.6 (CAN_H) and body ground.
OK: 4.5 V or less
(4) Voltage between the gateway-ECU connector terminal No.5 (CAN_L) and body ground.
OK: 4.0 V or less
(5) Disconnect the negative battery terminal.
Is the check result normal?
<4.5 V or less (CAN_H) and 4.0V or less (CAN_L)> The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction ).
<More than 4.5 V (CAN_H) or more than 4.0 V (CAN_L)> Check the BSW-ECU (master) connector, and repair if necessary. If the BSW-ECU (master) connector is in good condition, replace the BSW-ECU (master).