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Working on fix ECUs... AND FIXING WITH SUCCESS!!!

Started by Nacho-RT74, June 06, 2012, 12:53:32 PM

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Musicman

Quote from: ChargerST on June 08, 2012, 04:30:57 AM
Could you make a drawing of the circuit board and the components? My dad is a retired electronics teacher and he has got a cicuit board printer - need to give him something to keep him occupied  :icon_smile_big:

OOooooo.... I'd love to have a circuit board printer laying about..... Yea, that's just what I need, more side projects! :lol:
Cool idea though about the ECU boards, and it would be easy enough to do as it's a fairly simple circuit.... and it would give Dad something to do. Of course, if he's a retired electronics teacher I'm sure he'd be looking at ways to improve on it.

:cheers:

Musicman

Nacho

I've been looking at images of the MP boxes on the web, looking for part numbers on the power transistors, and it seems like every picture you look at shows a different part number, different place of origin, and a different manufacturer...  So much for Quality Control  :lol:

ChargerST

Quote from: Musicman on June 08, 2012, 07:35:01 AM
Quote from: ChargerST on June 08, 2012, 04:30:57 AM
Could you make a drawing of the circuit board and the components? My dad is a retired electronics teacher and he has got a cicuit board printer - need to give him something to keep him occupied  :icon_smile_big:

OOooooo.... I'd love to have a circuit board printer laying about..... Yea, that's just what I need, more side projects! :lol:
Cool idea though about the ECU boards, and it would be easy enough to do as it's a fairly simple circuit.... and it would give Dad something to do. Of course, if he's a retired electronics teacher I'm sure he'd be looking at ways to improve on it.

:cheers:

Haha, yeah, he likes to improve things. He designed a totally new (and different) circuit board for my tach (which was fried) - works flawlessly!

b5blue

Quote from: Musicman on June 08, 2012, 07:35:01 AM
Quote from: ChargerST on June 08, 2012, 04:30:57 AM
Could you make a drawing of the circuit board and the components? My dad is a retired electronics teacher and he has got a cicuit board printer - need to give him something to keep him occupied  :icon_smile_big:

OOooooo.... I'd love to have a circuit board printer laying about..... Yea, that's just what I need, more side projects! :lol:
Cool idea though about the ECU boards, and it would be easy enough to do as it's a fairly simple circuit.... and it would give Dad something to do. Of course, if he's a retired electronics teacher I'm sure he'd be looking at ways to improve on it.

:cheers:
You should have him do the gauge cluster boards! They are pricey!
  Nacho, check out Rick E. on eBay, (Ricks Mopar) he has 2 ECU's rated for 7200 RPM for sale at very reasonable pricing! Said in his listing they are made by "OEM Manufacturer"....Rick knows his stuff!

Nacho-RT74

Yes I know... with a decal HIREV 7500... I already have one of them... but... what can I say not convinced about them. I have been running one of them from January when my FBO unit broken up to two weeks ago, when went back to the Chromed box what just last long 24 hours... then replaced with an orange I also got to test it. ( I got on my last shipping 1 Chromed 1 Orange )

Talking about Performance by now the best two has been the FBO and the MP Chromed in that order but not by far... when worked LOL.
Venezuelan RT 74 400 4bbl, 727, 8.75 3.23 open. Now stroked with 440 crank and 3.55 SG. Here is the History and how is actually: http://www.dodgecharger.com/forum/index.php/topic,7603.0/all.html
http://www.dodgecharger.com/forum/index.php/topic,25060.0.html

Nacho-RT74

Printed circuit board diagram... dunno if I'll be able but will try.

First two days with the fixed Chromed box ( the one I didn't dissasemblied and last longed 24 hours ) and everything perfect. Fast response without miss a beat
Venezuelan RT 74 400 4bbl, 727, 8.75 3.23 open. Now stroked with 440 crank and 3.55 SG. Here is the History and how is actually: http://www.dodgecharger.com/forum/index.php/topic,7603.0/all.html
http://www.dodgecharger.com/forum/index.php/topic,25060.0.html

ChargerST

Quote from: Nacho-RT74 on June 08, 2012, 11:43:14 PM
Printed circuit board diagram... dunno if I'll be able but will try.


doesn't have to be perfect - actually i just need to know how the lines connect and the location of the pins - then I can draw the diagram myself. Here's the diagram I made for my tach (after a drawing my dad made of course ;) )

Musicman

Drawing the boards would be quite easy for me... I just need a good photo to work with... Here's a partial example using that dirty board from my previous post.

I start with the original image (the board would be all cleaned up of course).



Add the nodes and paths...



Remove the background, and there you have it!


ChargerST

So what's the real difference between the orange and the chrome boxes?

Nacho-RT74

BESIDE THE TRANSISTOR? good question! when I get some of the damaged orange box will know ( I know will get at least 3 )

Musicman, paths are on back of board ( on the FBO and old chrome box at least )
Venezuelan RT 74 400 4bbl, 727, 8.75 3.23 open. Now stroked with 440 crank and 3.55 SG. Here is the History and how is actually: http://www.dodgecharger.com/forum/index.php/topic,7603.0/all.html
http://www.dodgecharger.com/forum/index.php/topic,25060.0.html

Bob T

Hey Nacho, good to see you have some success there. I took these pics of some I have , they might be of use because the transistor # can be seen.
They are out of Chrysler Australia from the Valiant Charger and Regals

The Blue one is the current one in my 68 R/T, however I'm not sure which one I would use for a replacement if it failed, would probably try them all. Any clues?? Not to sure what the rev range is for the blue one and which would be the equivilent out of the others . Thanks
The red one has had a repair and needs to be siliconed up again
Old Dog, Old Tricks.

Musicman

Quote from: Nacho-RT74 on June 09, 2012, 10:48:33 PM
Musicman, paths are on back of board ( on the FBO and old chrome box at least )

Yes I know, but it doesn't really matter, it's still the same process, this was just used as an example.

Nacho-RT74

Venezuelan RT 74 400 4bbl, 727, 8.75 3.23 open. Now stroked with 440 crank and 3.55 SG. Here is the History and how is actually: http://www.dodgecharger.com/forum/index.php/topic,7603.0/all.html
http://www.dodgecharger.com/forum/index.php/topic,25060.0.html

Nacho-RT74

Bob T... sorry, don't know. A Real electronic tech will tell you better. I simply tried to match the existant
Venezuelan RT 74 400 4bbl, 727, 8.75 3.23 open. Now stroked with 440 crank and 3.55 SG. Here is the History and how is actually: http://www.dodgecharger.com/forum/index.php/topic,7603.0/all.html
http://www.dodgecharger.com/forum/index.php/topic,25060.0.html

Bob T

Quote from: Nacho-RT74 on June 10, 2012, 09:28:11 PM
Bob T... sorry, don't know. A Real electronic tech will tell you better. I simply tried to match the existant

Ok, no worries  :cheers:
Old Dog, Old Tricks.

Nacho-RT74

If somebody else tries to fix it like this and has success, please share it!
Venezuelan RT 74 400 4bbl, 727, 8.75 3.23 open. Now stroked with 440 crank and 3.55 SG. Here is the History and how is actually: http://www.dodgecharger.com/forum/index.php/topic,7603.0/all.html
http://www.dodgecharger.com/forum/index.php/topic,25060.0.html

ChargerST

Hey Natcho, did u get some orange boxes to do a comparison? If these boxes are pretty similar it would be cool to upgrade the orange ones to perform like the chromed boxes...

Nacho-RT74

will do soon, as soon my friend gets me the toasted ones he has ( 3 oranges I think )

( I already thought on that ;) )
Venezuelan RT 74 400 4bbl, 727, 8.75 3.23 open. Now stroked with 440 crank and 3.55 SG. Here is the History and how is actually: http://www.dodgecharger.com/forum/index.php/topic,7603.0/all.html
http://www.dodgecharger.com/forum/index.php/topic,25060.0.html

Nacho-RT74

It looks I began to miss some beats at high RPMs... maybe the Transistor is not the more adequate for this. ( or once again a quality issue )

will look further on test anyway to confirm this
Venezuelan RT 74 400 4bbl, 727, 8.75 3.23 open. Now stroked with 440 crank and 3.55 SG. Here is the History and how is actually: http://www.dodgecharger.com/forum/index.php/topic,7603.0/all.html
http://www.dodgecharger.com/forum/index.php/topic,25060.0.html

Mick70RR

I fixed my FBO ignition module today. First of all I changed the power transistor for an MJ10005 but it still didn't work. So I dug the rest of the black stuff out and noticed that the long wirewound resistor towards the middle of the PCB was open circuit. It's a 68 ohm resistor and looks to be about 5 watts. I found four 2 watt 68 ohm resistors at work so I wired them in series/parallel to give me 68 ohms at 8 watts and soldered them in. Tried it tonight and the car fired right up. Only tried it temporarily but I might bolt it in over the weekend and see how it goes on the road.
1970 Road Runner, 505 cid, 4 speed, GV overdrive, 3.91 gears
11.98 @ 117 on street treads

Nacho-RT74

Thats nice!

Nice update!

Maybe something to check on mine too ;)
Venezuelan RT 74 400 4bbl, 727, 8.75 3.23 open. Now stroked with 440 crank and 3.55 SG. Here is the History and how is actually: http://www.dodgecharger.com/forum/index.php/topic,7603.0/all.html
http://www.dodgecharger.com/forum/index.php/topic,25060.0.html

mhinders

I see a potential problem comparing the 2 transistors...

The gain is different in the 2 transistors...and it may work...and it may not work. It depends on how the circuit is designed, and how the components are chosen.
The MJxxx12 transistor has a higher gain than the MJxxx5 transistor (hfe, DC current gain). If the control current is on the low side in the design with the xxx12 transistor, the xxx5 transistor may not pull the full current. It's may however easily be fixed by putting a smaller value resistor on the transistor's base connection (getting a bigger control current).

The switching characteristics cannot easily be compared since the testing setup is different.
Martin
Dodge Charger 1967, 512 cui, E85, MegaSquirt MS3X sequential ignition and injection

Nacho-RT74

I used the 5 just because the other one wasn't available, and was for componment test what prooved ON MY CASE both modules failing on same component.

Now mick checked a diff component failure

MICK, which exactly resistor failed ? The pic posted by musicman is an FBO module
Venezuelan RT 74 400 4bbl, 727, 8.75 3.23 open. Now stroked with 440 crank and 3.55 SG. Here is the History and how is actually: http://www.dodgecharger.com/forum/index.php/topic,7603.0/all.html
http://www.dodgecharger.com/forum/index.php/topic,25060.0.html

Mick70RR

Quote from: Nacho-RT74 on October 17, 2012, 09:07:37 AM
I used the 5 just because the other one wasn't available, and was for componment test what prooved ON MY CASE both modules failing on same component.

Now mick checked a diff component failure

MICK, which exactly resistor failed ? The pic posted by musicman is an FBO module

It's the long open wirewound resistor right in the centre of the PCB. It had gone open circuit at one end. It looks like the legs are just crimped on, maybe that's the reason it failed.
1970 Road Runner, 505 cid, 4 speed, GV overdrive, 3.91 gears
11.98 @ 117 on street treads

nascarxx29

Anyone got a fix for this vintage ignition module.It to has a motorola transistor

transistorized ignition



http://www.dodgecharger.com/forum/index.php/topic,59561.0.html


1969 R4 Daytona XX29L9B410772
1970 EV2 Superbird RM23UOA174597
1970 FY1 Superbird RM23UOA166242
1970 EV2 Superbird RM23VOA179697
1968 426 Road Runner RM21J8A134509
1970 Coronet RT WS23UOA224126
1970 Daytona Clone XP29GOG178701