Caps Replacement : Code 7035

I've posted about this stuff before which can be reached here, but this time, I had the privilege of doing it to my ecu. Let me recall back the issue; if you owned a Mitsubishi car especially those 90's model, do take care of the capacitor in the ecu. Those caps are freaking vital such as vital as heart in human body. Do take note that Honda P30 ecus also exposed to this fragility too. One main reason is because, the capacitors used by the manufacturer were electrolyte type which uses an ionic conducting liquid as one of its plates. As this cap ages, so the body construction a.k.a the casing too. When a faulty capacitor is charged, the liquid-based electrolyte becomes unstable and breaks down, producing hydrogen gas. Since these types of capacitors are sealed in an aluminium casing, the pressure builds up within the capacitor until either the flat metal top of the capacitor begins to bend, or the rubber sealing plug is pushed down. Eventually the pressure exceeds the strength of the metal casing and venting occurs. When an electrolytic capacitor bursts, the acidic electrolyte will going to spill on the circuit board which eventually will further damage to the ecu.

There are 4 caps in 4G92 MIVEC ecu. When my ecu guru tested the caps, only 3 of them needs replacement while the other one seem perfectly working. A main reason why that one particular cap is still in mint condition is because it only regulate 5-volt connection while the other three were involve in higher voltage; 12V to be precise. The higher the voltage, the greater the strain the caps have to handle.

To make this post more dramatic, actually one of the three caps that have been replaced has shown some burn sign on the cap which indicate an "I've-replace-it-just-in-time-before-something-shit-happen" sign. This cap has served more than 10 years and as you may know, any electrical item with that kind of age can go nuts anytime without any further warning. Remember, it is way way much cheaper to replace those caps than to get another ecu; especially 4G92 MIVEC ecus. You've been informed.