ECU corrosion, when is it too late?

[Nuzzi]

I bought an ecu off ebay and of course the caps were leaking bad, there is a good amount of corrosion on surrounding leads/components. I cleaned it up with a toothbrush and baking soda/water mix, im just wondering if its even worth replacing the caps or if its already shot, its a 92/93 awd m/t turbo eprom so I would like to save it if possible. The seller "said" the car ran, my car isn't on the rd yet and the engine is apart so I cant test it other than just powering it on maybe. The board itself isn't peeling and the traces look intact, but until I remove the caps and clean it up more its hard to tell.

Here's a few pics, kinda hard to get in there with adequate light, the pics actually make it look worse than in person.

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[curt-s]

Can you post some high quality pictures?

If you're really unsure, you can have ECMTuning give it a go-over.

 

[Nuzzi]

pics added.

 

[curt-s]

Well, first off, I'd clean what I can and then break out the multimeter to test continuity of the trace from end to end (good) and any adjacent traces (bad). If you're still really unsure, get ECMTuning to look it over. It'll cost a little bit, but peace of mind is priceless

 

[steve]

I've repaired far worse in the past but you'll have to finishing cleaning off the conformal coating where the corrosion is. You'll also have to remove the heatsink to get at the corrosion under it and do a lot of desoldering to get at the electrolyte still under various parts.


You need to check the back side of IC110 to make sure the leakage hasn't eaten up the thin film resistors on the back or the pin mounting pads. If it has you'll need a good IC110 from another ECU.

Before you go any deeper, does it work now? Make sure there isn't an damage to the CPU or port expander (IC4 and IC5).

If you don't know that I'm talking about, send it to ECMTuning and let them fix it.

 

[Nuzzi]

Sounds good, ill dig farther into it and see what i can find. There is one surface mount resistor with the very top layer peeled off. It wasnt a huge setback if its bad. Thanks.