Is it manual or remote door locks? If manual I have the sections of the electrical manual that cover that. Don't have it for the remote door locks.
You should investigate the cause of the check engine light. Don't reset the ECM by disconnecting the battery. Have the trouble code readout with a scan tool that plugs into the diagnostic port under the dash. The trouble codes are formatted PXXXX, where XXXX is a number. Get that code, or codes if more than one, and post here and we can provide info on things to check.