I could really use some help on solving an issue that I’ve spent way too many hours on, I really enjoy solving issues like this but this one is beyond my knowledge. I have a 98 Toyota and it’s had the code C1225 “open or short circuit in solenoid SA1, I’ll say this vehicle has a pretty beefy abs/braking unit and I’ve gotten very familiar with it due to doing my own repairs on it over the years but I can’t run this one down so far. So under the hood the braking unit is made up of a hydraulic booster, pump motor and a box that houses the solenoids, inside the cabin under the gauge cluster is the ecu that controls the unit under the house so I guess my main question is in your opinion where would be the area that I should focus on the most for a open/short circuit dealing with the SA1 Solenoid? I’ll attach pictures on the pieces, the black box with like 7 resistors is the module under the hood that controls the solenoids and board with all the chips and hardware is the ecu inside the cabin, this way you’ll at least know what everything looks like. This may not be the right place for this but I know a lot of you are probably experts at circuits no matter the setting.

 

1998 Toyota, what model?

 

1998 Toyota, what model?

Land Cruiser

 

Have you actually identified which is solenoid SA1?
If so, can you disconnect one terminal of the coil and measure the coil resistance? Also, report the resistance of any resistor associated with that solenoid.

Transistor TR27 looks a bit cooked, or that may be just an image artifact.