Open in wire between IACV & ECM/PCM
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Open in wire between IACV & ECM/PCM
I recently got a p1519 (IACV Cuircuit Malfunction) in my 2003 Si. I followed these steps to diagnose the problem : http://www.hondafitjazz.com/manual/A00/HTML/98/SAA2E98K72100081143FAAT00.HTML
I got to step 13 and found not continuity between body ground and terminal A12. It tells me to "Repair open in the wire between the IAC valve and the ECM/PCM (A12).n" but I'm not really sure how to go about doing that. Any help, or comments appreciated.
I got to step 13 and found not continuity between body ground and terminal A12. It tells me to "Repair open in the wire between the IAC valve and the ECM/PCM (A12).n" but I'm not really sure how to go about doing that. Any help, or comments appreciated.
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Re: Open in wire between IACV & ECM/PCM
Ok, it's basically a 3 wire system...
The 3 wires are B+ (yel/blk), ground (blk), and a control or signal from the ECM (blk/red).
Which one is a problem? Did you confirm that wire is an open circuit?
The 3 wires are B+ (yel/blk), ground (blk), and a control or signal from the ECM (blk/red).
Which one is a problem? Did you confirm that wire is an open circuit?
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Im assuming its the signal wire (terminal 3 on my IACV connector). I grounded it with jumper wire (negative battery terminal disconnected) then checked for continuity on ECM connector terminal A12. There was no continuity, which means theres an open in the wire between IACV and ECM A12.
Im confused as to how I can verify and confirm theres an open. How do I trace that wire from the IACV to A12 or vice versa.
Im confused as to how I can verify and confirm theres an open. How do I trace that wire from the IACV to A12 or vice versa.
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I had the same code with a different car and it turn out to be a bad IACV. Just go to the junk yard and pick up one.
https://www.civicforums.com/forums/3...1519-code.html
https://www.civicforums.com/forums/3...1519-code.html
If you think a good mechanic is expensive, try hiring a bad one
Joined: Dec 2011
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From: Midwest. Aiming about mid-chest
Rep Power: 517 Re: Open in wire between IACV & ECM/PCM
Always confirm wire colors in a correct wiring diagram. It's too easy to hold a connector upside down or backwards and misdiagnose.
If you did the tests correctly, you have confirmed the open circuit. but it's darn easy to pick the wrong wires at the ECM, there are so many that look alike sometimes.
So if true, then the problem will be finding the open spot....it's somewhere between the ECM and the IAC valve. That black/red wire goes directly from the ECM to the IAC valve, there are no other connections shown for that wire in my diagram.
Look all along the harness bundle from the firewall and around the engine for rodent evidence, abrasion evidence, etc.
Might be easier/quicker to lay a new wire from "near" the ecm to "near" the iac. Make sure that's going to solve the problem before making it permanent. Splice where convenient.
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Rep Power: 0 Re: Open in wire between IACV & ECM/PCM
I had the same code with a different car and it turn out to be a bad IACV. Just go to the junk yard and pick up one.
https://www.civicforums.com/forums/3...1519-code.html
https://www.civicforums.com/forums/3...1519-code.html
