i took my car to get tested today and it didnt pass because they couldnt make a connection with my ecu. I have a JDM type s ecu currently in my car. Do USDM scanners communicate with JDM ecu's ? Also they said my voltage was to low and that it could be a fuse. Would this low voltage cause my ecu not to communicate with the scanner? if not what would cause my ECU not to communicate with the OBD scanner?

 

What year/model/engine ?

 

1999 prelude but i did a JDM type s complete motor swap with ecu

 

bump

 

It should connect to the computer scanner. OBD II is OBD II. It doesn't matter what country it came form. The low voltage could be the problem. Check your grounds and power cables, and get battery and alternator tested.

 

so a low voltage i.e. bad ground or blow fuse or bad terminals could cause my ecu not to make a connection with a scanner

 

OBDII is a North American protocol. Europe has there own system and I do believe Asia has there own system also.

 

So OBD II JDM ECU's will not work with USDM OBDII scanners?

 

So why are there JDM ECU's that are OBD2????? you are wrong. OBD systems are universal

To the OP: did you check your grounds and fuses yet? Try going to AutoZone and have them hook up their code reader to it. See if it will work or not.

 

Ya check all fuses and grounds and what-not and get it tested at autozone for free.

Thank god for OBD1

 

going today

 

Its still not reading i need to figure out weather or not its the JDM ecu that just cant be read by a USDM scanner ?

 

Ooooops My bad. The more I thought about it, I think the Type S ECUs are OBD1. Which means that they may not let you pass emissions if you live in a tough state. You have an OBD1 engine in a car that is supposed to be OBD2. They kinda frown upon that sort of thing. You should be able to hook up and OBD1 scanner to the car to get it tested (not sure if the plugs are the same or not from OBD1 to OBD2) but the thing is the emissions people are going to give you a rough time because OBD1 in America is on 1996 and older vehicles. The emissions standards for cars '97 and newer (OBD2) are a little more strict. You might possibly be up **** Creek. What state do you live in? You could tell them that the engine is from a 1996 Prelude VTEC, and that the original engine died and was replaced, but they may not go for it. Good luck.

 

can anyone else verify that a type s is OBD I ?

 

So i was thinking about changing ECU's and putting my stock SH ECU in. I was thinking if its the ecu then the stock ECU will be able to be read. But i dont know know if it will hurt my type S motor and if my car will pass because it might run like ****. Suggestions ? anyone know if a type s motor is OBD I or OBD II?

 

anyone ?

 

If I was in your situation I'd use the stock ECU.

 

i would try the stock ecu also. worst case try to find an emmisions tech that takes bribes.

 

Is my stock USDM ECU going to hurt my type S engine? The type s is higher compression and higher lift cams and most likely has different timing and fuel map.

 

anyone?