I'm trying to repair a car ECU that shows a fluctuating system voltage (between 6V and 13V in diagnostics) even though the battery voltage is stable. I suspect a faulty capacitor on the main power supply line.

The capacitors in question are a small, yellow, ceramic capacitor located right next to the main power input pin (pin 12) and ignition (pin 13) of the main controller chip. There are no visible markings or codes on it.

I've attached a close-up photo of the capacitors (pin 12 is constant + and pin 13 is ignition + ) and an overview of the board. I've checked the...