I'm hoping someone will be able to help me with this problem. The truck starts fine, but instrument panel completely dies and guages zero out when I release the emergency brake. When emergency brake is enguaged, guages work, but all MIL lights are always on. I ran scan on truck and DTC code thrown ia P1687 which makes sense. I then proceded to run EMIC test and it threw codes: 920,921,940,960,999. These codes suggest that the PCM and TCM aren't sending information to the EMIC. Just my guess. Sometimes odometer will read "NO BUS" after the scan. Can anyone offer me any suggestions? I'd hate to start replacing expensive control modules and the problem could be a simple ignition switch. Any advice would be appreciated.