DIY Honda ECU Repairs- P30 P08 P27

[EF_Hatch]

nope i didnt, engine is fresh built with high compresion 12:1 and light camshaft. i didnt rev it to high neither because right now it "runs" lean, of course i can't datalog with solid cel. i just started up engine for 30-50 seconds only.. tried many times with same problem..

 

[redzuana]

Hi,
Sorry because I cannot find a Toyota forum on ECU. So I come here. Can anyone or someone you know fix or diagnose my ABS ECU Toyota Altis 89540-12571? I suspect that the ECU got issue after the workshop did some ICE work and HKS power regulator to my car. Can PM or email the contact to me at [email protected]. Thanks.

 

[EF_Hatch]

Hi again E-tech, finally p06 trashed, i dont know why but after to work fine suddenly got solid cel...well, today i chiped a p28 manual ecu, i have to say i bought a moates engine sim for testing it faster,ok ,everything was fine, tested once i cleaned all solders,etc and worked fine with engine simu, vtec working,etc, had to go out , then im back for ago some minutes and tested it again, still worked good, but after 3 try, i get solid cel, i can't read code, it's solid cel, it worked good!!! i dontknow why right now is damaged, how's possible that?, cutted j1 and same problem, and after many trys, with j1 works ok again! but still solid cel with ji jumped, according engine sim, not pass 4.000rpm, ive been reading all thread and people talk about caps, what you means with all caps? ive seen about IC12 too, the p06 damaged, ic12 was too hot, not sure if that was the problem but right now i want to fix problem with p28 since that's my only ecu i have right now and wanna start and tune a car.

Hope your help, thank in advance E-Tech!!

 

[EF_Hatch]

im here again, ok, today i tested it and it works! but it's weird because after about 4-5 seconds get solid cel..not sure where would be the problem..tomorrow i will test it in the car but if you maybe can know where could be the problem please feel free to ask me for testing anything. Thanks E-Tech!

 

[E-Tech]

Hatch... after 4-5secs then got good chance to pull the error code.
With error code it is easier to troubleshoot....

 

[EF_Hatch]

thanks for your reply E-Tech, i do but it's solid cel..i can make a video with engine simulator and you can check what ecu do. if you need more pictures of this P28 i will do too.

Thanks alot!

 

[E-Tech]

thanks for your reply E-Tech, i do but it's solid cel..i can make a video with engine simulator and you can check what ecu do. if you need more pictures of this P28 i will do too.

Thanks alot!

I dun test with engine sim... i normaly test in my car...
Cel after car starts 3-4 secs will surely hv code.

Go do it in the car and telk me the code.

Do post a good picture of the top side of the board.
Pls mail to [email protected]...

Tq

 

[EF_Hatch]

Thanks, mail sent!!!

 

[ryand]

Hi e-tech,

been a long time since i logged in.

I got this p08 ecu rechipped. at key on feul pump prime and relay click, check engine light goes off. however after few seconds. check engine is ON. try to code it. it does not blink steady CEL.

I tried disconnecting J1 but same results. key ON, check engine goes OFF, then after a while steady CEL. No codes thrown

thanks

 

[E-Tech]

Hi e-tech,

been a long time since i logged in.

I got this p08 ecu rechipped. at key on feul pump prime and relay click, check engine light goes off. however after few seconds. check engine is ON. try to code it. it does not blink steady CEL.

I tried disconnecting J1 but same results. key ON, check engine goes OFF, then after a while steady CEL. No codes thrown

thanks

Can start? Can rev past 4000rpm?

 

[ryand]

Can start? Can rev past 4000rpm?

yes it can start but have not tried reving since i dont know the problem yet..

 

[E-Tech]

yes it can start but have not tried reving since i dont know the problem yet..

You are most likely in limp mode or backup mode.. it will not rev pass 4000.
If the ecu was good before chipping then you hv damaged the copper
trace some where...

Anyway need to be sure so slowing rev see if can pass 4000 to be
sure if u r in limp mode.

Btw hv u change all the caps? Any "brown" marks near the caps?

 

[ryand]

it worked before rechip then suddenly it threw a CEL.

i checked continuity from IC1 to hc373 to sst socket including test point. all was good.

220uF 35V cap damage the board but im sure there was no short or open trace near the area.

usually when there is an open trace, its a steady CEL upon key ON

However, for this po8 ecu, after key ON check engine goes off then comes back on after 5 sec. with no codes just steady CEL

I tested it with and without J1 shorted.

 

[E-Tech]

it worked before rechip then suddenly it threw a CEL.

i checked continuity from IC1 to hc373 to sst socket including test point. all was good.

220uF 35V cap damage the board but im sure there was no short or open trace near the area.

usually when there is an open trace, its a steady CEL upon key ON

However, for this po8 ecu, after key ON check engine goes off then comes back on after 5 sec. with no codes just steady CEL

I tested it with and without J1 shorted.

Anyway do the rev test....
Email me some good pictures too.
Tq

 

[ryand]

I did a rev test its goes past 4k rpm