AE101 ECU Capacitor Replacement
After the success of the AE92 ECU install, I decided to try replacing the capacitors in the original AE101 ECU.
What I found was rather disconcerting... A few of the capacitors had leaked and the dielectric had started to corrode the PCB. After a thorough wash and re laquer, I was ready to start.
The only capacitor I had trouble sourcing was the 20uF 50v. There is an abundance of 22uF, but nothing in 20uF. So I simply doubled up two 10uF 50v caps instead.
I sourced the capacitors from RS Components, as there is a trade counter near by. I chose Rubycon and Nichicon capacitors for their high quality and good reputation. All the capacitors are 105 degree rated to help ensure a longer lifespan in the rough environment they are to be installed in.
I have included the part numbers for all the caps, so you can take the list into the local trade counter (all parts are avaliable 'off the shelf') or you can order them online. They all only come in packs of five, so you will end up with spares. Good for if you stuff one up or you have mates with stuffed ECU's.
The following are the required tools to complete this mod:
- AE101 4AGZE MAP ECU.
- Soldering iron, solder, tinned wire, solder sucker, cutters, etc etc.
- PCB laquer spray
- Electronics cleaner spray
- Old Toothbrush
- Capacitors. See second list.
- A steady hand.
- Lots of patience and a bright light.
Capacitors:
- C002 - 47uF 100v - 193-7032
- C004 - 33uF 50v - 421-5098
- C010 - 20uf 50v - 224-4325 - (10uf 50v x 2)
- C011 - 100uF 25v - 421-7101
- C014 - 100uF 25v - 421-7101
- C401 - 15uF 63v - 491-0412
- C404 - 47uF 100v - 191-8081
First you need to remove the old electrolytic capacitors. I found a solder sucker to help immensely whilst doing this. Once you have them all removed, give the PCB a clean and a light scrub with the toothbrush if any corrosion is present. Rinse if need be and leave somewhere warm overnight to dry. If you only used the solvent, it should be dry in a few minutes.
Give the board a spray with the laquer to prevent further corrosion and let dry.
Now it's just a matter of installing the new caps. Make sure you put the right ones in the right holes, and get their polarity correct. The numbers and polarity are marked on the PCB, so double check everything as you go.
Below is the picture of the doubled up capacitors I mentioned earlier. I just soldered one in laying down, then soldered the other on top. A bit of superglue will help hold it in place until it is soldered.
And the result? While it unfortunatley didn't cure the power drop entirely, it did lessen it quite a bit. I also am happy knowing that my ECU won't be dissolving itself from the inside out anymore.....