Toyota ECM repair - SMD capacitor ID

[cmmar2016]

Greetings!

I'm trying to repair the computer for my 1997 Toyota. It has 2 failed (leaking/fried) capacitors #C120 & C116. C116 is a 10 mfd 10v 100C but I'm having trouble identifying the little SMD at C120. It's smaller than the ones listed at https://www.electronicspoint.com/resources/component-identification.44/

Can anyone help me ID this thing?

 

[davenn]

Can anyone help me ID this thing?

without circuit info .... nigh impossible

it could be anything from a few pF to 100nF

 

[cmmar2016]

Finding a manual for this thing isn't proving any easier...

 

[HellasTechn]

is it just me or have you removed a piece of the pcb together with the cap ? I am on cell phone so picture is not clear. I suggest you measure the cap with a capacitometer and based on the reading , estimate the original value. unless if it is blurged or dead in general

 

[HellasTechn]

for example of you read 39 uf it would most probably be a 47 uf. again that method I would use as last resort.

 

[cmmar2016]

is it just me or have you removed a piece of the pcb together with the cap ? I am on cell phone so picture is not clear. I suggest you measure the cap with a capacitometer and based on the reading , estimate the original value. unless if it is blurged or dead in general

I haven't removed anything accept the case cover for the ECM. It looks fried so testing may not yield any usable results.

 

[davenn]

is it just me or have you removed a piece of the pcb together with the cap ? I am on cell phone so picture is not clear. I suggest you measure the cap with a capacitometer and based on the reading , estimate the original value. unless if it is blurged or dead in general

for example of you read 39 uf it would most probably be a 47 uf. again that method I would use as last resort.

the electro's will have their values on them so they are not a problem to identify
C116 electro is definitely stuffed. I would replace all three of those electros 116, 118, 107

C120 is a SMD chip cap and will have a value range within what I suggested earlier
it's most likely a power rail decoupling cap so something like a 0.01uF (103) or 0.1uF (104)
would most likely work there




That transistor directly below C120 looks like it may have been getting hot. It doesn't have the nice shine all the rest do


Dave

 

[73's de Edd]

Sir cmmar2016 . . . . . .

ADDENDA . . . . . . .this info was poked up PRIOR to having the last new photo . . . . . .

Also I am NOW able to see tabbed surface mounted E-caps being used. By all means use conventionally leaded E-caps and trim excess lead length down to ~3/16 inch and put additionl L bends on their ends. Then position in the capacitor at a 45 degree angle to get good soldering tip clearance . . . . from any chance of burning the cases.
Reflow solder the caps end L bends to the pcb pads and then finally swing the caps to vertical up positioning.


You done GREAT on dead center of the photo, but, alas, lateral spatial distortion and reflected light fouled up our right frontal sections , MAIN area of interest.
I will guesstimate at the E-caps:
C116 being your canned unit and it looks like a BLUE C115 dry tantalum drop is being right beside it.
Looks like another E-caps C107 can is being at the forefront of the board, then a C116?18?being beside it.

Going back up to the left of the initial C116 I see a monolithic block SURFACE MOUNT multilayer ceramic capacitor with its assigned numbering as being C120.
If that unit willl cosmeticaly / chemically clean up of any residue oozed from C116, I would expect it to work just fine again.
Its function is to to shunt across an electrolytic, to additionally give the pair VERY good high frequency and " digital trash" suppression characteristics, by virtue of its inherently VERY low ESR characteristics.

You are ONLY mentioning C116, but in this circuitry I would EQUALLY be as suspect of the two OTHER E cans ALSO.
Look and see if they arent also, being of the same exact brand.

For your replacements, be sure to use beefier 105 deg cent temp rated units, with VERY low ESR specs.
Any chance that the elecrolytic leakage left a VERY dark black staining on the top of the PCB ?
I have found Nichicon brand units that, when they t leak, they leave almost indelible BLACK stains.

Does C120 look-a-like-a this . . . if so . . . . it is the type I mentioned and 99% of the units I see used in this application are being 0.1 ufd in their value.

73's de Edd

 

[davenn]

You are ONLY mentioning C116, but in this circuitry I would EQUALLY be as suspect of the two OTHER E cans ALSO.

as I said

Does C120 look-a-like-a this . . . if so . . . . it is the type I mentioned and 99% of the units I see used in this application are being 0.1 uF in their value.

as I also commented on

 

[Alec_t]

Is C120 in parallel with C107 across power rails (fat tracks)? If so I'd guess it's 100nF or thereabouts.

 

[HellasTechn]

is it just me or have you removed a piece of the pcb together with the cap ?

It's just that i see something that looks like it on picture of post #1 on the ruler under number 6.
Or is it just a hole on the ruler showing the PCB below ?

 

[davenn]

It's just that i see something that looks like it on picture of post #1 on the ruler under number 6.
Or is it just a hole on the ruler showing the PCB below ?

it's just you
as can be seen in post #6 the board below that point is complete

 

[cmmar2016]

Sir cmmar2016 . . . . . .

Going back up to the left of the initial C116 I see a monolithic block SURFACE MOUNT multilayer ceramic capacitor with its assigned numbering as being C120.
If that unit willl cosmeticaly / chemically clean up of any residue oozed from C116, I would expect it to work just fine again.
Its function is to to shunt across an electrolytic, to additionally give the pair VERY good high frequency and " digital trash" suppression characteristics, by virtue of its inherently VERY low ESR characteristics.

You are ONLY mentioning C116, but in this circuitry I would EQUALLY be as suspect of the two OTHER E cans ALSO.
Look and see if they arent also, being of the same exact brand.

For your replacements, be sure to use beefier 105 deg cent temp rated units, with VERY low ESR specs.
Any chance that the elecrolytic leakage left a VERY dark black staining on the top of the PCB ?
I have found Nichicon brand units that, when they t leak, they leave almost indelible BLACK stains.

Does C120 look-a-like-a this . . . if so . . . . it is the type I mentioned and 99% of the units I see used in this application are being 0.1 ufd in their value.

73's de Edd

It looks like most of the replacement cans I've seen so far are rated at 105 so that will be no problem there. And your C120 is so much prettier than mine but do you still feel I need not replace it?

 

[cmmar2016]

Is C120 in parallel with C107 across power rails (fat tracks)? If so I'd guess it's 100nF or thereabouts.

It is. It looks like it's a size 0805. I will probably buy an assortment just to be safe.


By the way, So sorry for the, eh, sorry photos...

If that unit willl cosmeticaly / chemically clean up of any residue oozed from C116, I would expect it to work just fine again.

What should I use to clean the board? And is there something I can use to reseal everything after I replace to capacitors?

The two small traces running under C116 are my only other concern. I'

I have limited electronic repair tools and no experience, so I'm shopping for tools and the components for this ECM and I'd like to get the best value for my money. All of the tool kits online seem to be of questionable quality. Any recommendations would be appreciated.

If I succeed with this I'll try to heal some of the other sick items accumulating in my garage (mostly flatscreen PC monitors).

Thanks for all the help!

 

[davenn]

but do you still feel I need not replace it?

do a gently clean around that area with a cotton bud and some methylated spirits to clean off the gunk
it may well be that the cap is still OK

 

[davenn]

What should I use to clean the board?

see my last post

And is there something I can use to reseal everything after I replace to capacitors?

you could if you wanted to just use a little spray on lacquer

The two small traces running under C116 are my only other concern. I'

do a photo of that with the cap out so we can check it