I have a circuit board with lots of soldered SMD chips. There are a few I2C components connected to the same bus and the bus is also connected to a "bus switch" isolation switch. Unfortunately the bus is behaving weirdly. It seems to have large capacitance, and my microcontroller seems unable to drive the clock signal low.
If this were on a breadboard I could simply remove components until it worked, and if it was a collection of components connected in series I could look at the signals between components to find where they go weird.
But unfortunately I can't modify the circuit (without a lot of effort anyway), and the components are all connected to the same bus.
Does anyone know of any clever ways of debugging this situation? Or would you resort to removing SMD components?
(By the way, this is one of the things I always hated about electronics - the implicit relationships between everything make it really hard to debug!)