Intermittent power failures... ABS, VSC, Tilt/Telescope, Door locks, No brake lights... All at once! (1 Viewer)

[Amptech]

Hello again!
I'm battling this intermittent bug which manifests itself usually when it rains. I had a leak previously, which led to a windshield replacement. That was about 3k miles ago, and the leak *appears* to be gone. However, today at the first sign of rain, the problem resurfaced. In the past, the issue usually resolves itself when the water "dries up."
Basically what happens is the VSC TRAC, ABS and VSC off lights all come on AND at the same moment the brake lights, tail lights, Fog lights, door locks, windows, and steering wheel tilt/telescope all stop working. The dash "BRAKE" light does not come on. Furthermore, if I turn on the headlights, they only stay in "High" mode and the tail lights don't come on either. The turn signals, reverse lights and hazards do still work. The vehicle still runs, drives and stops normally when coaxed out of Park with the over ride button- No ABS, tail lights or brake lights, obviously.
When the rain lets up a bit I'll go back and keep looking for leaks near the driver side kick panel, as I suspect water is somehow getting into the junction box or something.
But is there any particular relay or junction that might point to all these systems being triggered at once? I can't find any evidence of anyone having all these symptoms at once. Something in the firewall or under the hood perhaps?

Thanks all!

Notes: I have replaced(in the past year) all turn signal, brake/tail light bulbs, and headlamps with the exception of the 3rd Brake light. All were working in the moments prior to todays rain.
I also replaced the ABS/VSC computer with a used working one about 3k miles ago.

Updates: Today I checked the drivers kick panel and under dash area and found no evidence of leakage. I'm going to attempt to get a tech stream up and running on some type of device and see what that leads me to.
Connecting Pins E1&TC netted the following codes: 37(one tire different size) and 43(Deceleration sensor/harness). I did have a front tire with low pressure(now fixed), and tomorrow I'll address the Deceleration harness- clean and reassemble.

 

[Amptech]

Updates to my previous post(above):
Well, it continues to rain in NYC and the second I unlocked the driver's door with my key I could tell the problem had once again "miraculously" resolved itself. I put the key into the ignition and the started the vehicle and lo and behold everything was working as it should be. I cannot explain why eight or ten systems started working as suddenly as they stopped. The only hint of reason I can point to is that most/all of these systems run through the driver's side kick panel(and cowl) junction box- as per the EWD338U. Perhaps moisture crept in, or a relay is sticky, or a connector is corroded. I'll begin and update a list of things I've done to combat this issue as it arises, as I'm seeing lots of ABS and VSC threads lately.

But first, since everything was working properly, I decided to begin cleaning up connectors to see if any had noticeable corrosion. In fact, some did, to various degrees. The worst by far were the orange ones under the kick panel, right near the carpet. Lots of discoloration and some green corrosion residue. I used Deoxit D5 spray and wood cotton swabs to clean them up. I did the same for all the other connectors in the area as well. Some were worse than others. As I did this, I periodically turned the key to check what, if anything had stopped working.

I also cleaned the connectors and sockets on most of the kick panel junction box(the fuse side, not the cowl side). Most of these looked pretty good, and if problems persist, I suspect I'll be going back to finish the rest. One thing I imagine will need to happen in the near future is removing this junction box and addressing the relays on the cowl side.

Upon starting the car for the final time today, everything was still working normally. The same array of ABS/VSC lights came on for just a few moments but then shut off, so I imagine unplugging the majority of those connectors may have triggered a communication error which corrected itself.

I tested each system that had previously stopped working that now work: Headlights(high and low), Tail lights, Brake lights(including High Stop Light), Windows, Locks, Tilt/Telescope, AHC, Fog lights, ABS TRAC & VSC(I assume working, since lights are off) and shift lockout.

Things I did yesterday, between rain storms:
*Pulled and checked every fuse in the Driver's kick panel junction box- except for the 40 amp which I was unable to fully grasp to remove.
*Wiggled and/or pulled ABS relays in the Engine room junction box.
*Cleaned and Reoriented the Air filter
*Shorted E1 and TC resulting in codes 37 and 43.
*Added air to front tires(code 37)
*Visually inspected Brake switch and wiggled connector
*Changed Traction Control Module from 24/7 replacement back to the original one, on which I changed out the bad resonator.
*Wiggled the towing harness under the hitch.
*Attempted to clear codes by pressing brake 8 times- codes would not clear as I don't believe the brake pedal switch was getting any power.


Just a note, when I left the vehicle yesterday it was still non functional, but when beginning again today everything worked. We'll see how tomorrow goes!

I'll keep updating this thread as this issue progresses and gets better or worse!

Good luck!