i no that you can do it to obd1 but i was woundering if there is a war to convert a obd2 37820-p0h-315 auto ecu to manual? i searched everywhere any it seems like no one has the answer. i dont want to swap to obd1 because i want to save time in the furture. thanks agian

 

I do not believe that you can. There are enough significant differences that Honda issues unique PN's for Auto and Manual ECM's. Even more so with the '98 model years and later where they combined both the ECM and the TCM into a single unit.....

 

Hi, which car is this from?

I personally know one guy in Malaysia who had his gearbox changed to manual and still using the auto ecu. His car is a JDM EK3 with D15B 3 stage VTEC and CVT tranny converted to manual. As his car was OBD2A, the ECM (Engine Control Module) and TCM (Transmission Control Module) was a seperate unit.

The principle problems when retaining the auto ECM is that (assuming gearbox swapped and auto ECM used):
1. Car will start in P or N but will not rev pass 5KRPM and no VTEC
2. Car will not start in D but with full rev and VTEC functions
3. Other things i.e. ignition key mod, reverse switch bla bla bla etc I'll skip here.

Another guy from Thailand cranked the motor up without the TCM. The transmission technical manual stated the TCM receives information from transmission sensors and ECM input. That also means the engine will start with or without the TCM.

Basically the ECM has to be tricked to work in manual environment.

Getting manual ECU is ideal but ultra rare. Manual ECU have slightly different requirements than auto ECM. Auto ECM calls for 3 wire IACV and narrowband O2 whilst Manual ECU calls for 2 wire IACV and wideband O2.

OBD2B is different from 2A in a sense that the TCM and ECM are combined unit called PCM (Powertrain Control Module). I believe that the tricking process is the same but no solid proof yet.

This is my understanding for JDM D15B 3 stage only. Your vehicle may be different case than mine.

 

Just buy yourself a Manual OBD2B ECU (PCU) They are not hard to come buy. I did a search on Ebay and found 7-8 98-02 Manual Accord ECU's for under $100.

IIRC If you buy a manual ECU from North America I don't think it will be looking for a wideband O2 or 3 wire IACV unless it came out of an EX Automatic F23A4 ULEV Accord. I'm not 100% about the IACV though. Someone more in tune with the North American 98-02 Accord will have to chime in on that one.

 

I wouldn't know about Accords but for Civic finding a manual tranny ECU for D15B 3 stage VTEC in specific is very hard to come by.

There have been some examples of swaps where they retained the obd2 auto ECU and still manage to operate both VTEC-E & VTEC on the D15B 3 stage. Some wiring needed to be done to trick the ECU that everything is OK whilst using manual tranny.

Last night I tested this again on my 2b ECU by unplugging the 8 pin solenoid harness connector to simulate limp mode for the CVT.



The engine didn't throw a CEL but D indicator blinks constantly whilst still in P. The car will start. The manual states the CVT can still operate on full manual mode i.e. without TCM control / limp mode. I believe the same can be done on the Accord's auto ECU.

Changing to manual ECU is still the best option though auto ECU will suffice to some degree. Manual ECU will need 5 wire wideband O2 and 2 wire IACV as opposed to 4 wire narrowband O2 and 3 wire IACV.

I personally own a 37820-P2J-003 obd2a Manual ECU for my motor but I reckon maintaining the 2b auto ECU would be a quicker/cheaper route. I'm keeping the 003 just in case I really need it.

 

I sold my OBDII 5spd EX ecu for like $75

They're not hard to come by

 

But P2J-003 is =D

 

This is the Accord forum........


They're not rare or hard to come by haha. Half the information you posted doesn't really apply at all.

 

True true I'm just giving suggestions to the thread starter that worst comes to worst the auto ECU can still be used. Well at least for my case lol.

Thanks for the remind BTW

 

question guys..... i habe a 96 civic lx manual. I swapped to the d15b 3 stage vtech (2 stage some call it).

So, it runs decent on the regular ecu but i just got the p2j-003.

I havent installed the new ecu yet because its running fine at the moment and i have a potential problem i think i might run into.

So the d15b engine i got was an automatic engine.... what do i do about the iac?

Can i run the iac that came on the automatic d15b with the new p2j-003, and what do i do about the 2 and 3 wire connection difference?

 

1. this thread is 5 years old

2. this thread really has nothing to do with your question.

3. you should probably try posting your question in the Civic forum for better responses.

We don't deal with many 1.5L engines and ECU's here in the Accord forum.

 

I seriously wonder how people manage to find these threads, create an account, ignore their content, and then post random information.