F-CAN Circuit Troubleshooting
  1. Check for continuity between ECM/PCM connector terminal A4 and body ground.
Is there continuity?
YES -
Repair short in the wire between the ECM/PCM terminals A4 and the gauge control module, the VSA modulator-control unit, the yaw rate-lateral acceleration sensor, the EPS control unit, the SRS unit, the LKAS control unit (with driving support system), the ACC unit (with driving support system), the E-pritensioner unit (with driving support system), the navigation unit (with navigation system), or the DLC.■
NO -
Go to Step 47 .
  1. Reconnect all connectors.
  1. Connect the HDS to the DLC.
  1. Disconnect the gauge control module 32P connector.
  1. Turn the ignition switch to ON (II), and read the HDS.
Does the HDS identify the vehicle?
YES -
Replace the gauge control module. ■
NO -
Go to Step 51 .
  1. Turn the ignition switch to LOCK (0).
  1. Reconnect the gauge control module 32P connector.
  1. Disconnect the VSA modulator-control unit 47P connector.
  1. Turn the ignition switch to ON (II), and read the HDS.
Does the HDS identify the vehicle?
YES -
Replace the VSA modulator-control unit. ■
NO -
Go to Step 55 .
  1. Turn the ignition switch to LOCK (0).
  1. Reconnect the VSA modulator-control unit 47P connector.
  1. Disconnect the yaw rate-lateral acceleration sensor 4P connector.
  1. Turn the ignition switch to ON (II), and read the HDS.
Does the HDS identify the vehicle?
YES -
Replace the yaw rate-lateral acceleration sensor. ■
NO -
  • With navigation system: Go to Step 59 .
  • Without navigation system: Go to Step 63 .
  1. Turn the ignition switch to LOCK (0).
  1. Reconnect the yaw rate-lateral acceleration sensor 4P connector.
  1. Disconnect the navigation unit 32P connector.
  1. Turn the ignition switch to ON (II), and read the HDS.
Does the HDS identify the vehicle?
YES -
Replace the navigation unit. ■
NO -
Go to Step 63 .
  1. Turn the ignition switch to LOCK (0).
  1. Reconnect the navigation unit 32P connector (with navigation system) or the yaw rate-lateral acceleration sensor 4P connector (without navigation system).
  1. Disconnect EPS control unit connector D (28P).
  1. Turn the ignition switch to ON (II), and read the HDS.
Does the HDS identify the vehicle?
YES -
Replace the EPS control unit. ■
NO -
Go to Step 67 .
  1. Turn the ignition switch to LOCK (0).
  1. Reconnect EPS control unit connector D (28P).
  1. Disconnect SRS unit connector A (39P).
  1. Turn the ignition switch to ON (II), and read the HDS.
Does the HDS identify the vehicle?
YES -
Replace the SRS unit. ■
NO -
  • With driving support system: Go to Step 71 .
  • Without driving support system: Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM, then recheck. If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/PCM. ■
  1. Turn the ignition switch to LOCK (0).
  1. Reconnect SRS unit connector A (39P).
  1. Disconnect the LKAS control unit 26P connector.
  1. Turn the ignition switch to ON (II), and read the HDS.
Does the HDS identify the vehicle?
YES -
Replace the LKAS control unit. ■
NO -
Go to Step 75 .
  1. Turn the ignition switch to LOCK (0).
  1. Reconnect the LKAS control unit 26P connector.
  1. Disconnect the ACC unit 20P connector.
  1. Turn the ignition switch to ON (II), and read the HDS.
Does the HDS identify the vehicle?
YES -
Replace the ACC unit. ■
NO -
Go to Step 79 .
  1. Turn the ignition switch to LOCK (0).
  1. Reconnect the ACC unit 20P connector.
  1. Disconnect the E-pritensioner unit 14P connector.
  1. Turn the ignition switch to ON (II), and read the HDS.
Does the HDS identify the vehicle?
YES -
Replace the E-pritensioner unit. ■
NO -
Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM, then recheck. If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/PCM. ■