So I have a JDM motor and ecu, p72 OBD2a, and one of those damn check engine lights.
Went to autozone but couldn't get their device to read my codes. I am assuming because the ECU is JDM.

Is there any way to find out what the hell is making my car run like ****?

Thanks

 

Jumper the scs connector and count the flashes

 

go to somewhere other than autozone, theyre scanners are crap



you can do that obd2?

 

Yep above the passenger kick panel theirs a blue connector. Pull that down use a piece of wire or paper clip. Place it between the pins to complete the circuit. The check engine light will then flash and you just count the flashes

 

wrong, jdm ecus do not use us spec obd2 scan protocol. i know of no easy way to read one of these ecu's and i've never tried the flash game to see if it would work. what you would actually need is a scan tool that was compatible with whatever format is used in japan.

 

Then explain to me as to how I do this to pull my code. I'm itr swaped with a 96 spec motor trans and ecu. Pulled and did everything myself with a rhd front clip I purchased.

 

I've never had a problem with the Actron scan tools at Autozone and I use them just about every day. They're not top of the line, but they work just fine.

OBD2 scan tools will not read JDM (or EDM, I imagine) ECUs. JDM (and EDM) cars don't even have that 16-pin DLC under the dash that US cars have.

You can use the paperclip trick by jumping the 2-pin connector on the passenger side. This does work on OBD2 cars too. We've done this here at my house on an OBD2 US Honda with a JDM ECU.

 

aight thanks everyone ill do that paperclip trick

 

never knew you could do that to obd2 also...

the autozones next to where i live use a small palm scanner and none of the people there know how to use it, i usually have to operate it and the readings are vague, cant read any spec just tells you what cel code is on

if its plugs into a usdm car shouldnt it read it the ecu??

good scanners come with different formats, a import mechanic should have it, especially if he got a snap-on scanner

 

Even the smallest palm scanners work fine as long a they give you back a code.

You're missing something about Autozone. I understand most people wouldn't know this.

Okay, next time you get a P-series code from a scan tool (any scan tool - the codes are the same), write it down or remember it.

Go to Autozone. Get on one of them computers. You'll see at the top it asks for year, make, model, etc. Ignore that. Below those drop down menus is a big block of text listing car parts. Ignore that. Under that box of text is a white bar. Click on that and type in your code. Press Enter.

The computer will cross reference your code as a part number and trouble code.

The computer will list down the description for what the code means along with the most common causes for that code. It will even narrow the codes by the make of the vehicle (Domestic, Honda, Mitsubishi, Nissan, etc.)

If you press F8 it will print out that list. Sometimes (not very often) the list is too long and you'll have to write it down instead.

Autozone's trouble code information is actually better than what I normally can find online by Googling a code.

When I'm at home and need a definition for a trouble code (since I use the same tin code scanner I think you're talking about) I call Autozone and say, "I need you to look up a code for me". No problems at all getting them to look it up. If they don't understand how to look up a code, just tell them to look up a part number (and then IIRC you click on Trouble Codes after that).

Remember that Autozone is the McDonalds of car parts. There might be some incredible cooks at McDonalds, but they're still going to hire some people that don't know much of anything about making burgers.

As far as the DLC, the JDM ECU just plain doesn't use the DLC so when you plug a scan tool into the DLC it's just not going to read.

Btw, I work at Autozone and though it's far from a dream job, some parts of the business really do get a raw deal when talked about online.

 

iso 9001 is the standard scan tool format, it will not work on a jdm ecu. if i modus does, i'd be curious what format is needed to read a jdm ecu. yes everything plugs up fine, the scanner just sees a dead port. what format is your scanner using?

 

I'm not talking about plugging a tool in. I was talking about the 2 pin scs. The jdm as you explaint do not support the dlc.

I've been currious for a while to see their tools and wiring for their dlc.

 

Use the "paperclip trick".

Take a paperclip. Unfold it. Bend it into a U shape.

Find the 2 pin connector on the passenger side, on the right side of the glovebox. Sometimes you have to dig around a little to find it, but it's usually able to be found without even removing the glovebox.

Insert the ends of the paperclip into the 2 pins.

Turn the ignition power on. You don't even have to turn the engine on.

The check engine light will begin to flash. Count the long flashes. Count the short flashes.

Long flashes are the first digit. Short flashes are the second digit.

For example: _ _ _ _ . . . would be a 43

It's pretty easy to find the codes listed online. They're everywhere, but here's a link to one. https://honda-tech.com/forums/honda-crx-ef-civic-1988-1991-3/part-2-obd1-code-check-list-2568406/

You might want to watch the codes cycle a couple times to make sure you get all the codes.

 

For obd 1 they use a dlc, its a 5 pin connector on the obd1 cars as opposed to the three pin the U.S got. As far as obd2 jdm ecus they dont communicate with the standardized obd2 protocal as someone else said. I assume honda kept all the ecu plugs basically the same throughout the world as a matter of uniformity. The jdm obd2 ecus are basically obd1 ecus in a different case. I would bet the 5 pin dlc was carried over to obd2 jdm hondas in place of the 16 pin standardized obd2 connector. For the record even obd1 usdm hondas with the three pin dlc supply a ton of stream data, the only thing really missing that obd2 has is LT and ST fuel trim and calculated load values. As far as jumpin the two pin scs connector and reading the blinking basic codes, I've done that with usdm and jdm ecus in the same usdm car with no problem.