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Hey guys,
im going to pull my ecu today or tomorrow to check the cap quantities i need for my 95 LS. Is there any precautions i should take when opening my ecu to count my caps? Do i need a anti-static wristband before i open it up? Or can i just pop it open and count so i can order the caps?
Hey guys,
im going to pull my ecu today or tomorrow to check the cap quantities i need for my 95 LS. Is there any precautions i should take when opening my ecu to count my caps? Do i need a anti-static wristband before i open it up? Or can i just pop it open and count so i can order the caps?
no **** sherlock. I read the first post and it did mention something about the danger of static electricity so that is why i am asking. I won't be soldering myself but i do want to open the ecu to check cap quantities before i order.
Toyota has started to use Nichicon's electrolytic capacitors that containing “quaternary ammonium salt / compounds" in the late 80s and has kept using them for a bit more than a decade. The reason why they used those capacitors was simply because the internal impedance was low enough and showed good performance in removing noise and ripples at DC lines.
A little before that many electronics industries in Japan started to use similar capacitors that were for non automobile use and faced serious leaking problems in the early 90s. The details are written below but all in Japanese. http://ednjapan.com/edn/articles/1208/01/news006.html
I don't have the time nor the ability to translate all the contents so I will just translate the title. “80年代末期の“亡霊”に注意” or “Watch out for the “phantom” in the late 80s”
The “phantom” here means the electrolytic capacitor which contains infamous “quaternary ammonium salt / compounds". Judging from the title, it is dangerous to use this type of capacitor without taking any special precautionary countermeasures.
Most of the electronics companies in Japan stopped using this type of capacitor in the early 90s or mid 90s for fear of leaking problems. But many automobile industries kept using them because they needed good performance. Another reason was that they have been used in high reliability type-capacitors. Nichicon has been manufacturing special versions of this type for the automobile industries using specially coated lead wires with special sealing rubbers. One of my colleagues evaluated them and found the automobile type much better than those types designed for home appliances applications but the lifespan was not as long as those electrolytic capacitors that use regular liquids. Also the high reliability types were very expensive. I cannot show you the details of the evaluation results but what I can say is that the lifespan is longer than roughly 10 years or so but you cannot expect a lot if used for longer than that.
As I fix different ECUs as a volunteer, I came across many failed Nichicon's PF(M) type capacitors these days, some 12 years old, some 15 years old. What I can say now is that my colleague has done a good job evaluating the capacitors using an oven in the accelerated mode. In accordance with that and from my own actual experience, ECUs older than 12 years are ready to fail someday soon or later, that I can say with confidence.
Below is a failed capacitor used in a 97 Celsior. You can see how the leg has corroded and the part on the board where liquid has leaked out.
Those who want to replace Nichicon's type PF(M) capacitors to avoid future problems, be sure to use low ESR type capacitors. Never select capacitors just seeing the voltage and the capacitance. I recommend you to use Rubycon's type ZLH or Nippon Chemicon's type KZH. These do not contain infamous "quaternary ammonium compounds" but their ESR is low enough. You also have to pay good attentions against electric static discharge when doing the replacing job. A wrist strap is definitely needed to use. Without it you might damage the ECU.
Regarding capacitors Rubycon's type ZLH and Nippon Chemicon's type KZH, the availability in USA is not so good. LScowboyLS was kind enough to try to find capacitors that were OK to use and he listed up at the post #1. Those capacitors are good enough.
hi Yamae,
would i need the antistatic wristband to open the ecu to check cap quantities before i order? I have an electronics repair guy who is gonna perform the repairs on my ecu. I will provide him with the correct caps as you and LScowboy have suggested. Is it essential he use the same flux and rosin types LScowboy suggested(rosin core solder 63/37 (Radio Shack p/n 64-015 or equivalent) rosin solder flux (Radio Shack p/n 64-022 or CAIG DeoxIT rosin flux p/n RSF-R80-2) in the first post? I want to set this guy up for success.
thanks for your input
Last edited by Giorgio13; Dec 17, 2019 at 08:35 PM.
Reason: Adding info
would i need the antistatic wristband to open the ecu to check cap quantities before i order? I have an electronics repair guy who is gonna perform the repairs on my ecu. I will provide him with the correct caps as you and LScowboy have suggested. Is it essential he use the same flux and rosin types LScowboy suggested(rosin core solder 63/37 (Radio Shack p/n 64-015 or equivalent) rosin solder flux (Radio Shack p/n 64-022 or CAIG DeoxIT rosin flux p/n RSF-R80-2) in the first post? I want to set this guy up for success.
thanks for your input
It would be the best to ask LScowboyLS the reason why but he is not here any more. But he is rather active on the Facebook and you probably can confirm it.
As far as I help different repair jobs requested by local shop owners and dealer managers, I only use the solder called RH60-1.0-A which has the ratio of 60% and 40% because I only have this one as my stock. This solder had been widely used among Japanese electronics industries until the RoHS has started. I have been in use of this to fix old electronics gears that use the old lead containing solder. I never had any problem using this 60/40 solder so far and what I can say is that we don't need to worry about the ratio too much as long as the lead is contained. The RH60-1.0-A contains the flux inside too and I don't use any additional flux. The most important thing is not to use non lead solders, I'd say.
Last edited by Yamae; Dec 18, 2019 at 01:16 AM.
Reason: to add links
It would be the best to ask LScowboyLS the reason why but he is not here any more. But he is rather active on the Facebook and you probably can confirm it.
As far as I help different repair jobs requested by local shop owners and dealer managers, I only use the solder called RH60-1.0-A which has the ratio of 60% and 40% because I only have this one as my stock. This solder had been widely used among Japanese electronics industries until the RoHS has started. I have been in use of this to fix old electronics gears that use the old lead containing solder. I never had any problem using this 60/40 solder so far and what I can say is that we don't need to worry about the ratio too much as long as the lead is contained. The RH60-1.0-A contains the flux inside too and I don't use any additional flux. The most important thing is not to use non lead solders, I'd say.
Yamae,
i appreciate your quick response. Would you recommend me wearing anti static wrist band before opening the ECU to prevent damage to sensitive parts? Ill order some 60/40 solder as well.
i appreciate your quick response. Would you recommend me wearing anti static wrist band before opening the ECU to prevent damage to sensitive parts? Ill order some 60/40 solder as well.
thanks again
I definitely use a wrist strap to prevent the static charge problem. If it's not available, you will be able to use a thin copper wire and a series register of 100 to 1000 kilo ohms instead. All you need is to connect your body and the ground trace of the ECU board with it.
I definitely use a wrist strap to prevent the static charge problem. If it's not available, you will be able to use a thin copper wire and a series register of 100 to 1000 kilo ohms instead. All you need is to connect your body and the ground trace of the ECU board with it.
Got it. I will order the wrist strap today before opening this ecu. Thanks for your help sir. I'll give an update on my ecu repair.
Having major trouble getting the upper bracket on the ECM sorted.
Anyone who has actually done this on a 1998 know how to manipulate this upper bracket. You would think you could just slide the thing forward but that metal piece surrounding the bolt does not move enough to let it escape. It also doesn't seem to be attached to anything to take it out. At a loss.
Hi guys please don't destroy me too much, but this thread has a lot of useful info and I wanted to see if @Yamae could assist?
I have a 1994 Toyota Celica GT-Four WRC Edition. The car developed an inconsistent random misfire recently. Others had mentioned capacitors so I removed the ECU and found one that leaked. The others are still great. I looked for low ESR capacitors but the websites don't tell you if they are or not so it has me hesitant on purchasing some. These are the capacitors in my ECU. Can you help me locate the capacitors?
Hi guys please don't destroy me too much, but this thread has a lot of useful info and I wanted to see if @Yamae could assist?
I have a 1994 Toyota Celica GT-Four WRC Edition. The car developed an inconsistent random misfire recently. Others had mentioned capacitors so I removed the ECU and found one that leaked. The others are still great. I looked for low ESR capacitors but the websites don't tell you if they are or not so it has me hesitant on purchasing some. These are the capacitors in my ECU. Can you help me locate the capacitors?
Sorry that this is the LS400 Forum and we don't have the list for other models.
But about half of capacitors you need are listed in the post #1 of the thread. Other non listed capacitors for your Celica can be found searching for the Digikey.com. All you need to select is to find capacitors recommended series such as Rubycon ZLH/ZLJ, Panasonic FC/FR/FM, Chemi-Con KZM/KZH/KZE and Nichicon EP/PW/HW series.
Low ESR electrolytic capacitor are preferred and never use ceramic capacitors to avoid the phase rotation/oscillation problem.
Sorry that this is the LS400 Forum and we don't have the list for other models.
But about half of capacitors you need are listed in the post #1 of the thread. Other non listed capacitors for your Celica can be found searching for the Digikey.com. All you need to select is to find capacitors recommended series such as Rubycon ZLH/ZLJ, Panasonic FC/FR/FM, Chemi-Con KZM/KZH/KZE and Nichicon EP/PW/HW series.
Low ESR electrolytic capacitor are preferred and never use ceramic capacitors to avoid the phase rotation/oscillation problem.
@Yamae thank you for the reply. Looks like my capacitors are all on the list. However, the capacitors you posted seem to have a higher voltage rating. Is it okay to run higher voltage capacitors as long as the microfarads are the same? If so, is there a specific voltage range not to exceed? Thanks for the help.
@Yamae thank you for the reply. Looks like my capacitors are all on the list. However, the capacitors you posted seem to have a higher voltage rating. Is it okay to run higher voltage capacitors as long as the microfarads are the same? If so, is there a specific voltage range not to exceed? Thanks for the help.
The higher voltage caps on that list are fine to use.
I definitely use a wrist strap to prevent the static charge problem. If it's not available, you will be able to use a thin copper wire and a series register of 100 to 1000 kilo ohms instead. All you need is to connect your body and the ground trace of the ECU board with it.
hey Yamae,
so i opened up my ecu after i received my antistatic bracelet and wrote down the caps i need. For my 95 it was the exact number of caps specified in the first post. But as i was going to order the caps, LScowboy listed 100uf with 35v and 50v types. Will the 35v and 50v work in place of the 10v which are in my ecu? Thanks for your help. Next step is to order the caps.
The details are written below but all in Japanese.
In accordance with that and from my own actual experience, ECUs older than 12 years are ready to fail someday soon or later, that I can say with confidence.
