testing ECU to make sure it works?? now with WRITE UP :) and pics...
 

so i was watching my roommate assemble a MegaSquirt and got an idea...i need to make a 'simulator' (what the megasquirt guys call it) to test a ECU to make sure that they are working...

so here is my plan, and i need a little help.....oh yeah im talking about OBD1 Honda ECU;s (but im sure the idea would work with others too)... basicly i just want to make sure that the ECU turns on and isnt a solid CEL... so im guessing that i would just need a power (household 9v battery?), ground, CEL signal with an LED inline to the ground....that it?
i realize that when i plug this in it will throw a shitload of CEL's but thats the idea, if the LED blinks its a good ECU ;)

so am i on the right track here? will this work?

Re: testing ECU to make sure it works??
 

Just use a 12v battery.

Re: testing ECU to make sure it works??
 

well a 12v battery sitting in the living room doesnt make my roommates happy, somethign about non-sealed batteries and battery acid :-\

9v should be good enough to power up the ECU...

Re: testing ECU to make sure it works??
 

You can buy a 12v adapter from RadioShack.

Clip a harness from a junk yard car that will plug into your ECU, then you have the daunting task of emulating sensors.

Some of them can be hacked with various 5v potentiometers, however, OBD1 is very finiky about it's EACV. YOu might just actually have to hook that one up. When simulating an OBD0 ECU you can just splice a 10w10o resistor.. but that doesn't fool OBD1.

Anyway.. you should be able to simulate enough to get rid of the CELs with some afro-engineering.

Let me know if you need specifics that you can't figure out... I used to do this with OBD0 so I could test dataloggier for TE on my desktop inside my nice warm office. ;)

Re: testing ECU to make sure it works??
 

I was assuming that this would be somewhere other than the living room.

Re: testing ECU to make sure it works??
 

fine i can use a car battery, i jsut didnt want to go to the garage.... but not the point right now....

i need some help figuring out what wires i should be connecting where... ???

Re: testing ECU to make sure it works??
 

lol. Yeah the diehard on the coffee table is a good look.

Re: testing ECU to make sure it works??
 

On OBD0 ECUs I use the Radio Shack 12v power supply that i found for like $40.

Put power to A13 and ground to A16 and it will start up the ECU.

Throws code 6, 10 and 13 but at least you know your soldering and chip are good.

OBD1 I havent attempted to figure out yet...but like Parker says, get a junkyard harness and hook it up

screw the 12v battery...:)

Re: testing ECU to make sure it works??
 

thanks...thoughts are formulating...i still have my OBD0 to OBD1 jumper.... want to make a OBD0 tester also......

Re: testing ECU to make sure it works??
 

k, made a OBD0 test harness...------ easy (take pics later ;) ) 9v battery works fine... tested it on a PS9, solid CEL :-\

anyway i looked at my OBD0-1 jumper, got the wires i need.... but how does the CEL work on this? i have a little LED, but im not getting how i should be hooking this up in there?????