Short to GND in CAN Bus Line
CAN COMMUNICATION: CAN COMMUNICATION SYSTEM: Short to GND in CAN Bus Line
Short to GND in CAN Bus Line
DESCRIPTION
A short to GND is suspected in the CAN bus wire when the resistance between terminals 4 (CG) and 6 (CANH), or terminals 4 (CG) and 14 (CANL) of the DLC3 is below 200 Ohms.
WIRING DIAGRAM
INSPECTION PROCEDURE
NOTICE:
- Turn the power switch off before measuring the resistances of CAN bus main wires and CAN bus branch wires.
- After the power switch is turned off, check that the key reminder warning system and lighting system are not operating.
- Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not operate the power switch, any other switches, or the doors. If any doors need to be opened in order to check connectors, open the doors and leave them open.
HINT: Operating the power switch, any other switches, or a door triggers related ECU and sensor communication on the CAN. This communication will cause the resistance value to change.
PROCEDURE
1. CHECK FOR SHORT TO GND IN CAN BUS WIRE (DLC3 BRANCH WIRE)
(a) Turn the power switch off.
(b) Disconnect DLC3 branch wire gray connector E62 from the No. 1 CAN J/C "B" side (without earth terminal).
NOTICE:
- Before disconnecting the connector, make a note of where it is connected.
- Reconnect the connector to its original position.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance:
(d) Reconnect DLC3 branch wire connector E62 to the No. 1 CAN J/C "B" side (without earth terminal).
NG -- REPLACE DLC3 BRANCH WIRE OR CONNECTOR
OK -- Continue to next step.
2. CHECK FOR SHORT TO GND IN CAN BUS WIRE (NO. 1 CAN J/C WIRE)
(a) Disconnect CAN main bus wire white connector E42 from the No. 1 CAN J/C "A" side (with earth terminal).
(b) Measure the resistance between terminals 6 (CANH) and 4 (CG), and between terminals 14 (CANL) and 4 (CG) of the DLC3 each time a connector is disconnected.
Standard resistance:
OK -- CHECK FOR SHORT TO GND IN CAN BUS WIRE (NO. 2 CAN J/C WIRE)
NG -- Continue to next step.
3. CHECK FOR SHORT TO GND IN CAN BUS WIRE
(a) Disconnect connectors from the No. 1 CAN J/C one at a time.
HINT: Disconnect the ECU and sensor connectors other than the DLC3 branch wires and CAN main bus wires between the No. 1 CAN J/C and No. 3 CAN J/C.
(b) Measure the resistance between terminals 6 (CANH) and 4 (CG), and between terminals 14 (CANL) and 4 (CG) of the DLC3 each time a connector is disconnected.
NOTICE: Do not reconnect the disconnected connectors until this inspection is complete because there may be a short to GND in 2 or more CAN bus wires.
(c) When there is a short to GND in one or more of the bus wires that connect to an ECU (or sensor):
(1) Reconnect all of the connectors to the No. 1 CAN J/C, except for the one that was disconnected last (the bus wire that is shorted to GND). Check that the resistance shown on the tester is normal (200 Ohms or more) to confirm that there is a short to GND in one branch wire only.
HINT:
- The connectors connected to the No. 1 CAN J/C can be distinguished according to the color of the communication bus wires and the shape of the connectors.
- Reconnecting the connectors to non-specified positions on the No. 1 CAN J/C does not affect system operation. However, it is preferred to reconnect the connectors to their specified positions to avoid negative effects on the wiring such as tension on the wiring harnesses, and to make future maintenance easier.
NEXT -- Continue to next step.
4. RECONNECT CONNECTOR
(a) Reconnect the connector of the bus wire that is shorted to GND to the No. 1 CAN J/C (the connector that caused the bus wire resistance to change to 200 Ohms or more when it was disconnected).
NEXT -- Continue to next step.
5. CHECK FOR SHORT TO GND IN CAN BUS WIRE
(a) Disconnect the connector that includes terminals CANH and CANL from the ECU (or sensor) to which the bus wire shorted to GND is connected Symptom Related Diagnostic Procedures.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
HINT: If the resistance changes to 200 Ohms or higher when the connector is disconnected from the ECU (or sensor), there may be a short in the ECU (or sensor).
NG -- REPLACE CORRESPONDING ECU OR SENSOR BUS WIRE OR CONNECTOR
OK -- REPLACE CORRESPONDING ECU OR SENSOR
6. CHECK FOR SHORT TO GND IN CAN BUS WIRE (NO. 2 CAN J/C WIRE)
(a) Reconnect CAN main bus wire connector E42 to the No. 1 CAN J/C "A" side (with earth terminal).
(b) Disconnect No. 2 CAN J/C connector E41 (front of the vehicle).
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance:
OK -- CHECK FOR SHORT TO GND IN CAN BUS WIRE (A/C AMPLIFIER BRANCH WIRE)
NG -- Continue to next step.
7. CHECK FOR SHORT TO GND IN CAN BUS WIRE (NO. 2 CAN J/C WIRE)
(a) Disconnect No. 2 CAN J/C connector A40 (rear of the vehicle).
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- CHECK FOR SHORT TO GND IN CAN BUS WIRE (POWER STEERING ECU BRANCH WIRE)
OK -- Continue to next step.
8. CHECK FOR SHORT TO GND IN CAN BUS WIRE (HV CONTROL ECU MAIN BUS WIRE)
(a) Reconnect No. 2 CAN J/C connector A41 (front of the vehicle).
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
OK -- CHECK FOR SHORT TO GND IN CAN BUS WIRE (SKID CONTROL ECU)
NG -- Continue to next step.
9. CHECK FOR SHORT TO GND IN CAN BUS WIRE (HV CONTROL ECU)
(a) Disconnect HV control ECU connector A61.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- REPLACE CAN BUS MAIN WIRE OR CONNECTOR (HV CONTROL ECU - NO. 2 CAN J/C)
OK -- REPLACE ACCESSORY GATEWAY BRANCH WIRE OR CONNECTOR
10. CHECK FOR SHORT TO GND IN CAN BUS WIRE (SKID CONTROL ECU)
(a) Disconnect skid control ECU connector A74.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
OK -- REPLACE SKID CONTROL ECU ASSY
NG -- REPLACE SKID CONTROL ECU BRANCH WIRE OR CONNECTOR
11. CHECK FOR SHORT TO GND IN CAN BUS WIRE (A/C AMPLIFIER BRANCH WIRE)
(a) Disconnect No. 2 CAN J/C connector E41 (front of the vehicle).
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- CHECK FOR SHORT TO GND IN CAN BUS WIRE (A/C AMPLIFIER)
OK -- Continue to next step.
12. CHECK FOR SHORT TO GND IN CAN BUS WIRE (RADIO AND NAVIGATION ASSEMBLY BRANCH WIRE)
(a) Disconnect No. 2 CAN J/C connector E41 (front of the vehicle).
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- CHECK FOR SHORT TO GND IN CAN BUS WIRE (RADIO AND NAVIGATION ASSEMBLY)
OK -- REPLACE ACCESSORY GATEWAY BRANCH WIRE OR CONNECTOR
13. CHECK FOR SHORT TO GND IN CAN BUS WIRE (A/C AMPLIFIER)
(a) Disconnect A/C amplifier connector E38.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- REPLACE A/C AMPLIFIER BRANCH WIRE OR CONNECTOR
OK -- REPLACE A/C AMPLIFIER
14. CHECK FOR SHORT TO GND IN CAN BUS WIRE (RADIO AND NAVIGATION ASSEMBLY)
(a) Disconnect the radio and navigation assembly connector F12.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- REPLACE RADIO AND NAVIGATION ASSEMBLY BRANCH WIRE OR CONNECTOR
OK -- REPLACE RADIO AND NAVIGATION ASSEMBLY
15. CHECK FOR SHORT TO GND IN CAN BUS WIRE (POWER STEERING ECU BRANCH WIRE)
(a) Disconnect No. 3 CAN J/C connector A41 (front of the vehicle).
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
OK -- CHECK FOR SHORT TO GND IN CAN BUS WIRE (POWER STEERING ECU)
NG -- Continue to next step.
16. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN MAIN BUS WIRE)
(a) Reconnect No. 3 CAN J/C connector A41 (front of the vehicle).
(b) Disconnect No. 3 CAN J/C connector A42 (rear of the vehicle).
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance:
OK -- REPLACE CAN BUS MAIN WIRE (NO. 1 CAN J/C - NO. 3 CAN J/C)
NG -- REPLACE CAN BUS MAIN WIRE OR CONNECTOR (NO. 2 CAN J/C - NO. 3 CAN J/C)
17. CHECK FOR SHORT TO GND IN CAN BUS WIRE (POWER STEERING ECU)
(a) Disconnect power steering ECU connector A66.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- REPLACE POWER STEERING ECU BRANCH WIRE OR CONNECTOR
OK -- REPLACE POWER STEERING ECU