Inspection steps
WARNING: This page is about a different car, the 2014 Subaru BRZ. However, it is still accessible from the selected car via links, so may be relevant.
CAUTION:
- Before measuring the resistance of CAN bus, turn the ignition OFF and leave the vehicle as is for at least one minute without operating keys, switches, and doors. Disconnect the battery and wait for another one minute or more.
- If DTC related with CAN communication system is output, always start the troubleshooting according to the procedure described in "How to troubleshoot". (Refer to HOW TO TROUBLESHOOT )
- When the repair is complete, follow DTC check procedure to confirm the same DTC does not recur.
DTC check procedure: wait 10 seconds or more after IG ON
- After turning the ignition switch to OFF, you may have to wait for a while before disconnecting the battery terminals. Check appropriate precautions for battery terminal disconnection before proceeding. (Refer to WORKING PRECAUTIONS AND NOTES )
- Before performing troubleshooting, check the fuse for this circuit.
NOTE:
- Before disconnecting a connector, check for loose or unplugged connection by pushing back the connector case.
- After disconnecting the connector, make sure that its terminal and the case have no damage, deformation, or corrosion.
- Check for open circuit in CAN bus sub-line (Sub-line to the collation ECM (Smart key computer assembly))
- Disconnect the battery ground terminal, and then disconnect the vehicle harness connector D41 from the collation ECM (Smart key computer assembly).
- Measure the resistance between the terminals.RESISTANCE
Inspection terminals Inspection conditions Standard value D41-14 - D41-15 Disconnection of the battery ground terminal 57 to 63 Ω NG: Repair or replace CAN bus sub-line
Courtesy of SUBARU OF AMERICA, INC.
OK: Go to Next Step
- Check the wiring harness and connector (Power supply system)
- Measure the resistance between the terminals.RESISTANCE
Inspection terminals Inspection conditions Standard value D48-11 - chassis ground Disconnection of the battery ground terminal Less than 1 Ω - Reconnect the battery ground terminal.
- Measure the voltage between the terminals.VOLTAGE
Inspection terminals Inspection conditions Standard value D41-5 - chassis ground IG ON 11 to 14 V D48-2 - chassis ground IG OFF 11 to 14 V NG: Repair or replacement of wiring harness or connector
Courtesy of SUBARU OF AMERICA, INC.
OK: Replace the collation ECM (Smart key computer assembly)
- Measure the resistance between the terminals.