ECM Replacement
NOTE: If the troubleshooting leads to replace the ECM after substituting a known-good ECM, reinstall the original ECM first, then do this procedure.
  1. Make sure you have the anti-theft code for the audio.
  1. Connect the HDS to the data link connector (DLC) (A) located under the driver's side of the dashboard.
  1. Turn the ignition switch ON (II).
  1. Make sure the HDS communicates with the vehicle and the ECM. If it doesn't, troubleshooting the DLC circuit.
  1. Remove the battery.