ECM and TCM are under the hood in front of the fuse box, hidden by the black plastic cover
BCM is in the console under the radio

 

If the water did not get up to the BCM (passenger foot well fuse box) I can't think of any reason for no start. No crank, maybe.
The only things on the floor are ground points and wire harnesses.

The typical reason for the security light is low voltage. I would get my VOM out and check ever fuse, under hood, BCM and the one near the battery.
The fuse near the battery runs the computer part of the BCM, The fuses labelled "BCM" in the under hood box are power for the fuses on the BCM. The BCM controls the security light, that is why I am talking about it.

This appointment with shops 2-3 weeks out thing really confuses me. Been hearing it a lot, never experienced it. 2 months for a doctor, yes doing that right now. Mechanics are drive up service here. Insurance adjusters are "right now". I live in a small town 60 miles from DC and Richmond.

 

Hey Don
Aren’t those SRS modules, under the center console, sitting on the floor hump ? Would they be lower than the BCM ?

 

The SRS module is right behind the shift lever. I don't think it would inhibit starting. If the water swamped the shifter maybe the interlocks got mucked. Maybe the brake pedal position sensor?

 

Thank you for the responses, friends. As a current status update . . . the shop replaced and programmed the BCM with labor, testing, and troubleshooting . . . the total bill was $1125.00. Now we have the vehicle back and the airbag light is on and the display is indicating Service Airbags. Further, the brake lights work but only come one when the pedal is fully depressed. Also, the rear wipers are completely inoperative. Final item is the AC is not working. Technician indicated that perhaps there is a refrigerant leak as he indicated that the AC should be fine electrically. Tried to add a can of R-134A when we got home with it, but low side pressure was 150+ PSI. Bled off the excess pressure but the AC still did not work even after getting the low side pressure down in the green range to 40 PSI. Will take it back to the shop Monday with the list of these four items to address and resolve (hopefully at no extra cost.) AC, brake lights, rear wipers, and air bag light all were fine and worked properly before the flash flood. Hope these can be easily resolve without much (ideally any additional cost.)

Thank you again for your comments and advice. Interested to hear any further advice, comments, and/or recommendations.

 

Why was the BCM replaced? Unless they gave you some proof it was bad, you got soaked. Did it get submerged?
What is the coolant temperature? P0128 (low coolant temp) will disable AC. Could be the temp sensor got soaked.
Brake pedal sensor got soaked. Rear wiper switch got soaked or disconnected by buffoons.
The water got deeper than you said.
If it got into the shifter area the airbag "brain" SDM got destroyed. There are a couple of airbag connectors under the front seats and under the front kick panels.

 

Thank you for the reply. BCM got soaked which is why it was replaced which was what was needed here. Prior indication (from me) was that water was about half way up on the tires and about 4 inches above the bottom of the doors. Technician reports that photos indicate that it reached the bottom of the dash. Not sure about that as the seats would have been soaked if it were up that far and they were not. Either way the BCM could have (and did) get wet. Technician reported visible indications that the BCM had shorted out and testing further confirmed. Technician sent 37 photos to insurance adjuster who strongly favored total loss. We pushed back on this and pushed for repair and return to operational service.

Right now, all keys work, FOB works, drives fine as before flood. Amazing progress. Encouraging. Coolant temperature gauge indicated in the normal operating range (needle is right about in the middle after warm up.) Going to check the rear wiper fuse under the hood. Was weird about AC low side being 150+ lbs. Does BCM control AC system? Did tech miss a programming item or two?

Regarding brake pedal senor, seems like it works since the brake lights illuminate when the pedal is fully depressed but wonder if the sensitivity could be adjusted so that the brake lights also light up when the pedal is partially depressed.

 

The brake pedal position SENSOR is a variable resistor, not a on/off switch.
If water got that high, any sensor or switch that got wet could be damaged. Including the AC pressure switch and the AC switch on the dash and the rear wiper switch and the blower switch. The AC won't run unless the blower is blowing. That should be included in the insurance fix.
The
Don't bother looking at the analog temp gauge, it is useless. The digital temp is what counts.
Does the cooling fan still work?

How are you going to keep the title clean after a flood event? Doesn't MO keep track, CarFax certainly will? The car will be valued scrap, maybe that is a good thing if they tax you on value.

 

Thank you for the reply, Don. Sounds like the brake pedal sensor might need to be replaced. Cabin air blower is working fine. Blows air from min to max and moderate depending on switch setting. No AC though (AC worked fine before flood.) Coolant temperature is 171 F from the information center (not the analog needle.) Think cooling fan is working as coolant temp remains steady after warm up on this 88 F day (and stays steady while driving.) Checked fuse for rear wipers. Looked fine. Removed and replaced relay as well (unable to tell anything about condition.) You are right that these items should be paid by insurance (we paid our deductible directly to the shop and paid for replacing both lower control arms, alignment, and tire rotation.)

So, we purchased in February after it had been totaled before due to right front collision damage. We replaced some parts from junkyard and a few new parts (5 total) and had it inspected by the State. Then submitted our inspection report and paperwork to get a salvage title updated to prior salvage. While waiting for this to come back from the State, the flash flood happened. So, title is not super clean anyway.

 

Coolant temp is way too low. Looking at the fan while the temp is 171F tells you nothing.
One more time:
The t-stat opens when the coolant reaches 180F. It must do it within a calculated period based on cubic feet of air consumed.
The fan turns on when the coolant reaches 219F
The fan turns off and the t-stat closes when the temp gets back down to 180F.
"Normal" operating temp is around 190F.
If the temp is that low there will be a pending P0128 and no AC.

I didn't know you could get insurance on a salvage vehicle.