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+--- Thread: IACV explained (/showthread.php?tid=5244)
RE: IACV explained - max - 02-20-2018
(02-20-2018, 06:37 AM)Lord Popgun_imp Wrote: I have sent Sportsterdoc the info he requested and I would suspect he will post on it later. I would, but I’m letting Max and Doc do the posting. They are better at it
Changing or getting to the IACV is a LOT of work. Thus the heavy labor charge. Just accessing the connector is easy as Doc has shown.
Thanks Popgun, for Dave's info i will post part of an e-mail sportsterdoc sent me that describes the access to the iacv connector;
Lift tank, remove right side throttle body cover
Using right hand, depress connector locking tab with thumb, press, then lift up.
Wish removing IACV were that easy!
iacv connector in place
![[Image: 7f5f109edca4b41e9fecd28c6abf8a73.jpg?1]](https://cb1100forum.net/forum/uploads/imp/201802/7f5f109edca4b41e9fecd28c6abf8a73.jpg?1)
iacv connector removed
![[Image: ff5d709c60ef6c678ee5284a11cdfbae.jpg]](https://cb1100forum.net/forum/uploads/imp/201802/ff5d709c60ef6c678ee5284a11cdfbae.jpg)
Tadaa.
RE: IACV explained - SportsterDoc - 02-20-2018
Max, thank you for posting the photos of the IACV on my 2014 standard.
Popgun, thank you for info from FSM pages 5-41 and 5-42
Below are a condensation of those pages:
Note: These tests may be done with IACV mounted, by lifting rear of fuel tank and removing right side throttle body cover.
1. After clearing stored DTC, per page 5-14, recheck for stored DTC 29-1. If none, then prior DTC was intermittent.
2. Measure resistance of each of the four wires at the ICAV connector (disconnected, harness side, not IACV side). Continuity to ground should be infinity. If not, the wiring harness has a short to ground.
3. Check continuity to ECM, from disconnected ECM 33 pin connector to disconnected IACV 4 pin connector
Positions are numbered with locking tab up:
ECM A6 black/yellow to IACV connector postion 1 (left)
A17 black/red, position 2
A16 black/blue, position 3
A7 black/orange, position 4 (right)
4. Measure IACV resistance, (IACV side, disconnected), facing with locking tab up at airbox side (mirror image of connector):
position 4 black/yellow (right)
position 3, black/red
postion 2, black/blue
position 1, black orange (left)
a. black/yellow to black orange (2 outside positions), 99-121 ohms at 77F/25C
b. black/red to black/blue (2 inside positions), 99-121 ohms at 77F/25C
If resistance out of spec, FSM declares IACV faulty
My 2 cents: If IACV and wiring tests good, then if symptoms point to IACV, it may be a piston travel issue or air port issue.
RE: IACV explained - dave - 02-20-2018
Hi Doc, thank you again for all of your help. I don't mean to sound dumb, but can you please clarify how to perform step #3? I assume the ECM is somewhere beneath the seat, and can be easily accessed, or you would have provided instructions for how to locate it. A picture of the disconnected ECM 33 pin that shows the locations of A6, A17, A16, and A7 would be worth a thousand words. Does the ECM 33 pin need to be disconnected from the ECM to perform these resistance tests?
My bike has never exhibited an error code, except when I unplugged the EOT sensor; do I need to perform step #1?
I will perform these tests, but first I would like to clean all of the connections you described in a different post (or maybe it was a PM?). I can clean each connector and perform a test separately, if this would help generate information for the team. I would have to ride the bike about 10 miles after each connector was cleaned to perform any kind of a meaningful test, so it would take me one day between each test. Please advise.
Thanks again to the entire team. I can't remember the last time I have seen such incredible team work!
RE: IACV explained - SportsterDoc - 02-21-2018
(02-20-2018, 12:06 PM)Dave_imp Wrote: Hi Doc, thank you again for all of your help. I don't mean to sound dumb, but can you please clarify how to perform step #3? I assume the ECM is somewhere beneath the seat, and can be easily accessed, or you would have provided instructions for how to locate it. A picture of the disconnected ECM 33 pin that shows the locations of A6, A17, A16, and A7 would be worth a thousand words. Does the ECM 33 pin need to be disconnected from the ECM to perform these resistance tests?
My bike has never exhibited an error code, except when I unplugged the EOT sensor; do I need to perform step #1?
I will perform these tests, but first I would like to clean all of the connections you described in a different post (or maybe it was a PM?). I can clean each connector and perform a test separately, if this would help generate information for the team. I would have to ride the bike about 10 miles after each connector was cleaned to perform any kind of a meaningful test, so it would take me one day between each test. Please advise.
Thanks again to the entire team. I can't remember the last time I have seen such incredible team work!
3. Check continuity to ECM, from disconnected ECM 33 pin connector to disconnected IACV 4 pin connector
Positions are numbered with locking tab up:
ECM A6 black/yellow to IACV connector postion 1 (left)
A17 black/red, position 2
A16 black/blue, position 3
A7 black/orange, position 4 (right)
A sketch of ECM connector is on page 5-41 of FSM and the details of section 3, including isolating the ECM connector to IACV connector.
The ECM is under the fuel tank, per FSM 17-2 diagram.
(02-20-2018, 12:06 PM)Dave_imp Wrote: Hi Doc, thank you again for all of your help. I don't mean to sound dumb, but can you please clarify how to perform step #3? I assume the ECM is somewhere beneath the seat, and can be easily accessed, or you would have provided instructions for how to locate it. A picture of the disconnected ECM 33 pin that shows the locations of A6, A17, A16, and A7 would be worth a thousand words. Does the ECM 33 pin need to be disconnected from the ECM to perform these resistance tests?
My bike has never exhibited an error code, except when I unplugged the EOT sensor; do I need to perform step #1?
I will perform these tests, but first I would like to clean all of the connections you described in a different post (or maybe it was a PM?). I can clean each connector and perform a test separately, if this would help generate information for the team. I would have to ride the bike about 10 miles after each connector was cleaned to perform any kind of a meaningful test, so it would take me one day between each test. Please advise.
Thanks again to the entire team. I can't remember the last time I have seen such incredible team work!
Need to, no, but it would be interesting to know if a 29-1 code was ever set
(02-20-2018, 12:06 PM)Dave_imp Wrote: Hi Doc, thank you again for all of your help. I don't mean to sound dumb, but can you please clarify how to perform step #3? I assume the ECM is somewhere beneath the seat, and can be easily accessed, or you would have provided instructions for how to locate it. A picture of the disconnected ECM 33 pin that shows the locations of A6, A17, A16, and A7 would be worth a thousand words. Does the ECM 33 pin need to be disconnected from the ECM to perform these resistance tests?
My bike has never exhibited an error code, except when I unplugged the EOT sensor; do I need to perform step #1?
I will perform these tests, but first I would like to clean all of the connections you described in a different post (or maybe it was a PM?). I can clean each connector and perform a test separately, if this would help generate information for the team. I would have to ride the bike about 10 miles after each connector was cleaned to perform any kind of a meaningful test, so it would take me one day between each test. Please advise.
Thanks again to the entire team. I can't remember the last time I have seen such incredible team work!
When you disconnect the IACV, if it looks sanitary, you may not need to do anything. If you see any signs of corrosion or crud, then contact cleaner and perhaps a soft tooth brush would be helpful. Same with ECM connector. Both are sealed connectors...so, main concern may be a damaged/tweaked contact.
If the IACV stepper is cycling (stepping/attempting to step) then wire continuity is not likely an issue...unless a break makes contact intermittent.
First recommended step is to simply disconnect IACV, inspect wires and contacts, clean as appropriate, then reconnect and go for a ride.
RE: IACV explained - SportsterDoc - 02-26-2018
Looking at the throttle body assembly on-line, it appears that the assembly is very complete, not only including the TPS, IACV, but all the hoses, tubes, pipes, 4 way and 5 way vacuum fittings, and even fuel injectors. No wonder is it a "fix".
http://www.2wheelpros.com/oem-parts/2014-honda-cb1100-throttle-body-assembly.html#
For those cured by throttle body assembly replacements, note that doing so eliminates, for their application, the following:
1. ECM
2. ECM program (unless a new program loaded with the TB replaced)
3. MAP
4. EOT
5. IAT
related wiring and connectors
4800 miles since 7 Nov 2017
only ran errands today (~40 miles), 48 MPG, typical 51 MPG
Cycle Gear has a sale on Freeze-Out thermals
Already had the pants/long johns (block the wind through jeans, very well)
Got the long sleeve T for $19.97 (67% off).
Not many sizes on the rack, but can be ordered on-line.
Hoping to go across the desert to Los Angeles in a couple weeks.