P1509 iacv malfunction

SHUSS2012

MEMBER
1996 HONDA CIVIC
275,336 MILES

I have tried changing the engine harness 3 times with new harness' I have replaced iacv sensor with 7 new sensors. I have tried 6 different ecu (pcm) (computers) tried changing pgmfi main relay. Tried changing 02 sensors. The voltage on a 3 wire iacv is supposed to be 4.9 on orange wire. Battery voltage on yellow with black stripe wire. And 10.33 volts on the black with blue stripe wire at normal operating temperature. I have traced all the wires and have continuity on all wires. But the problem seems to be that all 3 wires are getting straight battery voltage.

6 Replies

FIXITMR

MECHANIC
9,990 POSTS

I would definately stop the changing as it's not helping?

Was this

answer

helpful?

Yes

Monday, May 7th, 2012 AT 7:20 PM

SHUSS2012

MEMBER
3 POSTS

I just want it to be clear that everything has been tried.

SPONSORED LINKS

Was this

answer

helpful?

Yes

Monday, May 7th, 2012 AT 7:22 PM

FIXITMR

MECHANIC
9,990 POSTS

Did you acquire the vehicle in this condition?

Was this

answer

helpful?

Yes

Monday, May 7th, 2012 AT 7:29 PM

SHUSS2012

MEMBER
3 POSTS

Yes.

Was this

answer

helpful?

Yes

Monday, May 7th, 2012 AT 7:33 PM

ASEMASTER6371

MECHANIC
52,797 POSTS

Wow, I think you created more issues than solving anything.

If it was me, I would put everything back to original and start the checks with all original wiring. There is an issue with either the wiring or the pcm. You cannot swap out pcms like you did as they will never work due to flashing.

Roy