Brake system code (1 Viewer)

[ChaseTruck]

2004 GX470, 133k miles; on rare occasions, I get ABS, VSV TRAC and VSV OFF lights on. They typically go off by themselves after a little while, in the same drive cycle. Gas cap pretty new, just went through Louisiana testing without a hitch.

Lexus sez there's a code C1246, skid control ECU (in the DS kick panel?) needs to be replaced, parts cost ~$2,700, and I'm not feeling it right now...

Searching the web netted this:
C1246 - Master Cylinder Pressure Sensor Malfunction
C1246 Possible Causes
Faulty Skid Control ECU or Brake Actuator
Skid Control ECU or Brake Actuator harness is open or shorted
Skid Control ECU or Brake Actuator circuit poor electrical connection

I tend to go with option #3 at this point in time; used versions of the skid control ECU go for ~$100 on ebay...
Two questions:
1. Before I dig into stuff - any advice from the board?
2. Is there an easy way to read brake system codes? I understand my OBDII reader (UltraGauge Blue) isn't going to cut it for this?

 

[GXO]

Could be a short at the ABS controller. The screws underneath are notorious for rusting out

 

[ChaseTruck]

Thanks - without being able to look at the FSM right now, that's the one next to the brake master cylinder?

 

[GXO]

Yes. Will have to reach under an pop the rubber boot and snap a pic with your phone

 

[ChaseTruck]

So we have some resolution to this issue:
I learned how to red codes with the paperclip method, confirmed code 46/46
Price LeBlanc Lexus, Baton Rouge: we'll have to change the brake computer, $3,000
Earnhart Lexus of Scottsdale: no way; we've never had to change a brake computer on any GX since they came out.
Road trip from LA to AZ (our 'wheeling base is there...), warning lights gone again; miss hurricane Laura by a day, I-20 past Abilene, but then go on Hwy 380 from the panhandle of TX across NM, and Hwy 60 into AZ. Super scenic.
Earnhart Lexus of Scottsdale: faulty brake switch at pedal; code results from contrasting input to brake computer from brake pressure sensor and brake pedal switch. Replacement of brake pressure (~$380) switch resolved the code.
Return trip imminent, planning to spend some time in Big Bend National Park along the way.