Electrical nightmare

[richcu]

Please any ideas. Our 2004 Tahoe has these symptoms. The following will not work or does not work. 1.All gauges except (speedometer and tac) do not work. 2. all door locks do not work 3. radio does not work 4. obd code readers will not pick up any signals 5. 4 wheel drive module will not work 5. battery light is on all the time (alternator tests good 4 times at autozone). 6. Today there was a complete loss of the gas pedal, would not increase rpm just would idle. We disconnected the battery then reconnected the battery then it worked again. 7. all windows will not work. 8. abs light is on all the time. 9. air bag light is on all the time. none or the safety buzzer things work.
We have replaced the ignition starter switch.
It is a 2004 Tahoe with flex fuel 5.3 ltr. We have tried for two days to diagnose with no results. I tried to find the grounds and check them out but I do not know where they all are. Some of our area mechanics say, BCM, grounds, instrument cluster and ignition starter switch. I can not get into the 2 area dealers till the end of next week.
Any ideas???

 

[gdddup]

did this happen before or after starter switch was replaced

 

[richcu]

Before, we replaced it to hopefully fix the problems but no go.

 

[2005yukonxl]

have you owned this all along or buy it this way? park it in a flood lately?

 

[richcu]

Owned about 2 years, no water no flood, just driving on a good day and the whole instrument cluster when blank, came back on then these problems remained

 

[DenaliAK]

May need a new PCM or whatever the computer is called in these things. That is some major failure, and without codes is just weird....

 

[Thumper8302]

id def say body control module