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Engine **FIXED** Code 67 preventing KOER test... but clutch is pressed and A/C is deleted??

  • Thread starter Thread starter TomOsiris
  • Start date Start date Jun 21, 2022
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Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,252
17,937
224
Massachusetts
Jun 23, 2022
#21
  • Jun 23, 2022
  • #21
Open means no connection, no continuity.
 

Dan02gt

mazing how much gas smell came from that tiny hole
20+ Year Stangneter
Mar 2, 2003
909
415
113
Greenville, NC
Jun 23, 2022
#22
  • Jun 23, 2022
  • #22
So I had a weird issue with mine a few years ago and spent days troubleshooting why the system wouldn’t work correctly. I determined it was a damaged wire coming off of pin 46 somewhere in the wiring harness. I fixed it by clipping the wire coming out of pin 46 a few inches away from the computer connector and ran a new wire that I connected to the neutral sensing switch connector that is in the center console for the auto cars. This fixed my problem. If I ever pull the dash out I’ll go through the wiring until I find the issue with the original wire.
 

TomOsiris

Member
May 19, 2019
68
16
18
CT
Jun 24, 2022
#23
  • Jun 24, 2022
  • #23
Dan02gt said:
So I had a weird issue with mine a few years ago and spent days troubleshooting why the system wouldn’t work correctly. I determined it was a damaged wire coming off of pin 46 somewhere in the wiring harness. I fixed it by clipping the wire coming out of pin 46 a few inches away from the computer connector and ran a new wire that I connected to the neutral sensing switch connector that is in the center console for the auto cars. This fixed my problem. If I ever pull the dash out I’ll go through the wiring until I find the issue with the original wire.
Click to expand...
Aren't there other wires that also ground thru pin 46 though?
Wouldnt cutting that wire and going straight to the neutral switch lose your ground for everything else, ECT, TP, ACT, ?

Or did you just like T-tap into the wire and connect it as a secondary?
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,252
17,937
224
Massachusetts
Jun 24, 2022
#24
  • Jun 24, 2022
  • #24
TomOsiris said:
Aren't there other wires that also ground thru pin 46 though?
Wouldnt cutting that wire and going straight to the neutral switch lose your ground for everything else, ECT, TP, ACT, ?

Or did you just like T-tap into the wire and connect it as a secondary?
Click to expand...


You aren't necessarily clipping it out in the sense of elinimating it. You are just splicing in another leg for the circuit that the grounding circuit can use to complete. In other words, if you identify that one section of your wiring is damaged, you connect the new wire at a god known point ahead of the damage, and behind it.


To go back to that wiring diagram which is pretty marked up at this point. Lets say the wire was broken in the big red splotch and you lost the connection there. You would tap the new blue wire in at two known good points and just go around the break. See how the path of the blue wire adds an additional parh for the circuit to complete, but doesn't interfere with the other sensor taps for pin 46.

 
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TomOsiris

Member
May 19, 2019
68
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Jun 24, 2022
#25
  • Jun 24, 2022
  • #25
Mustang5L5 said:
You aren't necessarily clipping it out in the sense of elinimating it. You are just splicing in another leg for the circuit that the grounding circuit can use to complete. In other words, if you identify that one section of your wiring is damaged, you connect the new wire at a god known point ahead of the damage, and behind it.


To go back to that wiring diagram which is pretty marked up at this point. Lets say the wire was broken in the big red splotch and you lost the connection there. You would tap the new blue wire in at two known good points and just go around the break. See how the path of the blue wire adds an additional parh for the circuit to complete, but doesn't interfere with the other sensor taps for pin 46.

Click to expand...
ok this definitely makes sense to me.
in the post above when he said "clipping" I thought he literally meant cutting the wire at the ECU and running directly to the sensor.
I might end up doing something similar temporarily, but I'm pretty meticulous so I assume I will have to pull the dash and chase the harness, but not during driving season.
That can wait until winter.
Thanks again, I will be diving into the car deep this weekend, wish me luck!
 

TomOsiris

Member
May 19, 2019
68
16
18
CT
Jun 24, 2022
#26
  • Jun 24, 2022
  • #26
This is my car in case anyone as wondering
 
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Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,252
17,937
224
Massachusetts
Jun 24, 2022
#27
  • Jun 24, 2022
  • #27
Very nice
 
Reactions: TomOsiris

Dan02gt

mazing how much gas smell came from that tiny hole
20+ Year Stangneter
Mar 2, 2003
909
415
113
Greenville, NC
Jun 24, 2022
#28
  • Jun 24, 2022
  • #28
TomOsiris said:
Aren't there other wires that also ground thru pin 46 though?
Wouldnt cutting that wire and going straight to the neutral switch lose your ground for everything else, ECT, TP, ACT, ?

Or did you just like T-tap into the wire and connect it as a secondary?
Click to expand...
You are correct. I didn't have a wiring diagram in front of me when I made that post. I didn't cut 46, that's the signal return and cutting it would cause a ton of issues. I cut the wire coming out of pin 30, capped the harness side of the wire, and connected my new wire to the wire coming out of the computer connector. You could just use a T tap if you wanted to. My new wire runs to the connector that is in the center console and used for the auto cars and is part of the system. I used a T tap on it there.
 
Last edited: Jun 24, 2022
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TomOsiris

Member
May 19, 2019
68
16
18
CT
Jun 24, 2022
#29
  • Jun 24, 2022
  • #29
Dan02gt said:
You are correct. I didn't have a wiring diagram in front of me when I made that post. I didn't cut 46 that's the signal return and cutting it would cause a ton of issues. I cut the wire coming out of pin 30, capped the harness side of the wire, and connected my new wire to the wire coming out of the computer connector. You could just use a T tap if you wanted to.
Click to expand...
Thanks for the clarification.
I am going to test for continuity from the clutch switch wires back to pins 30 and 46, respectively.
I highly doubt BOTH of them are broken/disconnected, so I should be able to get away with a jumper wire setup similar to yours until I can diagnose the issue hiding somewhere in the harness..
 

TomOsiris

Member
May 19, 2019
68
16
18
CT
Jun 27, 2022
#30
  • Jun 27, 2022
  • #30
Mustang5L5 said:
Damage risk is low since we are dealing with grounds here, but my worry is false continuity readings through the ECU throwing off what you are trying to chase down.

I do have a spare A9L on the shelf. I can confirm in a bit that 30 and 46 are normally open.
Click to expand...
Update - codes are fixed!

After getting some good advice here I spent the weekend testing continuity to and from the ECU and the various switches shown in the diagram.
However, what is not shown in the diagram is that pin 30 also connects to the o2 harness, where there is a jumper wire that loops back into itself in few different ways for either a t5 or AOD transmission.

That is why some people had a code 67 after swapping T5 to AOD, or vice versa.

I tested everything there and it seemed ok, so I reconnected and pulled the codes again just out of curiosity.
no code 67!

I should also mention the reason why it was so important for me to get rid of code 67, this code will prevent you from running KOER tests, which I needed to do test and eliminate some other issues I was having (code 41/91, lean readings at both o2 banks)

Well, after reconnecting the o2 harness, not only was code 67 cleared, but the o2 codes were gone as well!
I have determined that although the o2 harness was connected, it was not fully seated to the point where the clip would lock it together, and therefore the connections were not 100% and sending inconsistent signals back to the ECU.

Big thanks to anyone who posted here to help, as going through the process of recommendations I received is what led me to this fix.
Glad to be back out on the road with confidence.
 

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Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,252
17,937
224
Massachusetts
Jun 27, 2022
#31
  • Jun 27, 2022
  • #31
Glad you found it.
 
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TomOsiris

Member
May 19, 2019
68
16
18
CT
Jun 27, 2022
#32
  • Jun 27, 2022
  • #32
Mustang5L5 said:
Glad you found it.
Click to expand...
Thanks for the help!
Gonna chalk this one up as a good learning experience
 

wbrockstar

Member
Mar 31, 2010
45
5
18
Nashville, Tn
Dec 3, 2022
#33
  • Dec 3, 2022
  • #33
Mustang5L5 said:
You aren't necessarily clipping it out in the sense of elinimating it. You are just splicing in another leg for the circuit that the grounding circuit can use to complete. In other words, if you identify that one section of your wiring is damaged, you connect the new wire at a god known point ahead of the damage, and behind it.


To go back to that wiring diagram which is pretty marked up at this point. Lets say the wire was broken in the big red splotch and you lost the connection there. You would tap the new blue wire in at two known good points and just go around the break. See how the path of the blue wire adds an additional parh for the circuit to complete, but doesn't interfere with the other sensor taps for pin 46.

Click to expand...
You're great at explaining things with easy to understand analogies/ visual reference.Thats up there in Jrichker territory.

I was a nuclear missile technician onboard SSBN submarines & studied/ applied electronics daily,but the instructors in SWSE (strategic weapons systems electronics) school & the weapons officer(s) onboard went completely by the book with only one means of describing a particular problem/ circuit.The learning curve was tough at times with the Navy's method.

Great job man
 
Reactions: limp and Mustang5L5

wbrockstar

Member
Mar 31, 2010
45
5
18
Nashville, Tn
Dec 3, 2022
#34
  • Dec 3, 2022
  • #34
TomOsiris said:
This is my car in case anyone as wondering
Click to expand...
Just curious.
What's your spring setup (coilovers, lowering springs,etc)?? The rims/color look good too against the black.
 

wbrockstar

Member
Mar 31, 2010
45
5
18
Nashville, Tn
Dec 3, 2022
#35
  • Dec 3, 2022
  • #35
TomOsiris said:
Update - codes are fixed!

After getting some good advice here I spent the weekend testing continuity to and from the ECU and the various switches shown in the diagram.
However, what is not shown in the diagram is that pin 30 also connects to the o2 harness, where there is a jumper wire that loops back into itself in few different ways for either a t5 or AOD transmission.

That is why some people had a code 67 after swapping T5 to AOD, or vice versa.

I tested everything there and it seemed ok, so I reconnected and pulled the codes again just out of curiosity.
no code 67!

I should also mention the reason why it was so important for me to get rid of code 67, this code will prevent you from running KOER tests, which I needed to do test and eliminate some other issues I was having (code 41/91, lean readings at both o2 banks)

Well, after reconnecting the o2 harness, not only was code 67 cleared, but the o2 codes were gone as well!
I have determined that although the o2 harness was connected, it was not fully seated to the point where the clip would lock it together, and therefore the connections were not 100% and sending inconsistent signals back to the ECU.
Click to expand...
Oh yeah,many Foxbody owners have felt the pain of that notorious jumper wire on the o2 sensor harness.
It has cooked thousands of ECU's over the years by being in the wrong terminal on the harness plug,for the ECU application.

The hood light harness plug has also cooked a bunch too,by mistakenly being used instead of the sti terminal to initiate a code scan.

Both of the above instantly fries pin 46's trace on the ECU,which basically creates a open in that circuit.Every component that's tied into that circuit fails to work or works incorrectly.Every sensor that has a signal return wire will fail to give correct readings.
 
Last edited: Dec 3, 2022

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,252
17,937
224
Massachusetts
Dec 3, 2022
#36
  • Dec 3, 2022
  • #36
wbrockstar said:
You're great at explaining things with easy to understand analogies/ visual reference.Thats up there in Jrichker territory.

I was a nuclear missile technician onboard SSBN submarines & studied/ applied electronics daily,but the instructors in SWSE (strategic weapons systems electronics) school & the weapons officer(s) onboard went completely by the book with only one means of describing a particular problem/ circuit.The learning curve was tough at times with the Navy's method.

Great job man
Click to expand...


Thank you sir. I appreciate it
 

limp

wrap a little cheese around it and its a done
5 Year Member
Oct 4, 2020
5,466
2,899
173
Florida
Dec 3, 2022
#37
  • Dec 3, 2022
  • #37
wbrockstar said:
You're great at explaining things with easy to understand analogies/ visual reference.Thats up there in Jrichker territory.

I was a nuclear missile technician onboard SSBN submarines & studied/ applied electronics daily,but the instructors in SWSE (strategic weapons systems electronics) school & the weapons officer(s) onboard went completely by the book with only one means of describing a particular problem/ circuit.The learning curve was tough at times with the Navy's method.

Great job man
Click to expand...
Based on your explanation of doing it ONLY one way on a Nuke, I would think that would be best dealing with nuclear missiles and a boat that goes under the water..... LOL
You caught me watching Red October.......
 

wbrockstar

Member
Mar 31, 2010
45
5
18
Nashville, Tn
Dec 25, 2022
#38
  • Dec 25, 2022
  • #38
limp said:
Based on your explanation of doing it ONLY one way on a Nuke, I would think that would be best dealing with nuclear missiles and a boat that goes under the water..... LOL
You caught me watching Red October.......
Click to expand...

It's funny/ironic you mentioned that you were watching Red October as I'm watching the very same movie at this moment.They ran it back to back for the 4th time over the last 4 weekends.


Believe it or not,there is more than one way to do certain things involving the Trident ll missle,but the main concern is that you pay attention to detail when working on/around all 24 of them.......
 
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