A few weeks back I went for drive (45 Mins ), temp outside was 90 + , was running A/C car ran great. Parked the car left the windows down a crack and left it for about an hour. Went to leave and the car was dead ! no interior lights , no radio , no windows, no locks , no crank . In key position 2 the dash was lit but nothing worked. I checked the battery and it was fully charged. Had to have car towed 30 miles . When we were taking the car off the flat tow truck we had to put the car in neutral . As soon as we turned the key everything came back on . Like normal !! Car cooled down on the tow home ??Some history , 2 months ago I had a stalling issue and no start , I changed the ignition switch and was back in business. I am showing no codes in PCM and TCS 1 in the BCM B3091 H ( can seem to find this code ) several in the SDM , IPC , LDCM and RDCM. Any thoughts would be welcome.

 

We'll see what other folks think, but what you describe, I'd look at that new ignition switch or the possibility that there was another underlying issue there as opposed to the heat. Everything you describe could be due to ignition switch not sending power in ACC, RUN, or Start. Good luck on this one!

 

Suggest before replacing anything in the future, try squirting some CRC Mass Air Flow Sensor Cleaner into the ignition. I had start problems several years ago and did the CRC squirt. No further start problems. Now I do the squirt as a semi annual maintence procedure.

 

Moved to C5 Tech for additional suggestions.

 

I second the notion of the Ignition switch, many c5 owners have had trouble with new Ignition switches straight out of the box.

 

Thanks for the suggestion. What keeps puzzling me is with no key in the ignition , why no interior lights ? Does the ignition switch control that ?

 

Were they turned off? From my '04 owner's manual.

Interior Lamps
Instrument Panel Brightness
The **** for this feature is
located on the left side of
the instrument panel.
Push the **** to release it from the stored position.
Turn the **** clockwise to brighten the lights or
counterclockwise to dim them.
Be sure not to have this **** turned all the way down
with the lamps on during the day. Your Driver
Information Center (DIC) may not be visible.
Parade Mode
The instrument panel brightness **** has an added
feature called parade mode to assist you in seeing
certain instrument panel controls if your headlamps are
on in the daylight. Turn the **** counterclockwise to
dim the instrument panel lights or clockwise to brighten
the lights. This will occur only with the parking lamps
or headlamps on.
Courtesy Lamps
When any door or the hatch/trunk lid is opened, the
interior lamps will go on unless it is bright outside.
You can also turn on the courtesy lamps by turning the
instrument panel brightness **** all the way clockwise.
Exit/Entry Lighting
With entry lighting, the interior lamps will come on when
entering the vehicle. The interior lamps will come on
for about 20 seconds when the key is turned to OFF or
a door is ajar.
You can turn exit and entry lighting off by quickly turning
the headlamps on and off or by quickly turning the
courtesy lamps on and off.

 

The Ignition switch has a contact specifically for detecting that the key is or is not inserted in the Ignition switch, that switch is a input to the BCM which then controls the interior lights if the key has not been inserted, and wakes up the car when the key is inserted. So it's either the switch or the BCM that is not working correctly.

 

Thank you , I agree with you with being either switch or BCM. When the problem occurred, the inside of the car was over 100 degrees . It was sitting in full sun windows up on a 90 degree day. Does heat play a roll on either the ignition switch or BCM ? How do you know if you need your BCM serviced ? Can I send it out some where to have it reprogramed or fixed ? Does anyone know the BCM code B3091 H ?

 

Temperature shouldn't have anything to do with what you experienced, I always recommend G7 Computers, you can contact them and send them your BCM for testing and repairs if needed.

 

Possibly relevant, not too many other hits on 3091:

https://www.corvetteforum.com/forums...c5-code-c.html