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T5 swap gone bad

  • Thread starter Thread starter dwith66
  • Start date Start date Jul 24, 2020
D

dwith66

Member
Jun 16, 2019
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Stoddard, Wisconsin
Jul 24, 2020
#1
  • Jul 24, 2020
  • #1
Hey guys, just finished the AOD to T5 swap on my 92 conv. Using the A9P computer, changed the 02 sensor harness to the correct one for manual and installed the factory T5 harness. Problem is I have no start, no crank, no headlights, no fuel pump run, nothing. Obviously, all this worked fine before the swap. I checked/replaced the neutral safety switch pretty sure that's not the problem. Everything is hooked up the way it should be as far as I can tell. Any ideas on what to check next? Confused
 

General karthief

wonder how much it would cost to ship you a pair
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#2
  • Jul 24, 2020
  • #2
Start with the battery connections and work your way to the ignition switch.
 
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D

dwith66

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Jun 16, 2019
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Stoddard, Wisconsin
Jul 24, 2020
#3
  • Jul 24, 2020
  • #3
Battery connections are good, engine ground is good, How do you know if the ignition switch is bad?
 

90sickfox

Wasn't a pretty sight...and I've got big hands
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#4
  • Jul 24, 2020
  • #4
What year is your car ?
 

General karthief

wonder how much it would cost to ship you a pair
5 Year Member
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polk county florida
Jul 24, 2020
#5
  • Jul 24, 2020
  • #5
Using a test light follow battery power from the battery to the solenoid, starter, then to check the ignition switch pull the plastic piece under the steering column and there is a connector/switch on the column under the dash, they are prone to failure.
 
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General karthief

wonder how much it would cost to ship you a pair
5 Year Member
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polk county florida
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#6
  • Jul 24, 2020
  • #6
More detailed instructions:

No Crank Checklist

No Crank checklist for 5.0 Mustangs Revised 24-Oct-2013 to update voltage drop figures. No crank, slow crank and stuck starter solenoid problems have the same root causes – low battery voltage and poor connections. For that reason, they are...
www.stangnet.com
 

General karthief

wonder how much it would cost to ship you a pair
5 Year Member
Aug 25, 2016
27,871
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polk county florida
Jul 24, 2020
#7
  • Jul 24, 2020
  • #7
90sickfox said:
What year is your car ?
Click to expand...
92 convertible
 
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D

dwith66

Member
Jun 16, 2019
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5
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Stoddard, Wisconsin
Jul 24, 2020
#8
  • Jul 24, 2020
  • #8
Thanks for the advise and the checklist, I'll check the connections maybe something's lose.
 
D

dwith66

Member
Jun 16, 2019
5
5
13
Stoddard, Wisconsin
Jul 24, 2020
#9
  • Jul 24, 2020
  • #9
Cars running! Cleaned all the connections and replaced the ignition switch for good measure. Thanks to General Karthief for the help!
 
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General karthief

wonder how much it would cost to ship you a pair
5 Year Member
Aug 25, 2016
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polk county florida
Jul 24, 2020
#10
  • Jul 24, 2020
  • #10
I just pointed my finger, you did all the work
 
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Mstng93SSP

You have a nice rear end there Dave.
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#11
  • Jul 25, 2020
  • #11
Just a sidenote, with an A9P you should not have changed to the 5 speed O2 harness. The computer/ecu dictates the O2 harness, not the trans. A9P uses an AOD O2 harness and an A9L uses a manual 5 speed O2 harness. You can run a 5 speed on an A9P with an Auto O2 harness with no issues.

Chris
 
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ZephyrEFI

Active Member
Mar 9, 2019
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Shakopee, MN
Jul 25, 2020
#12
  • Jul 25, 2020
  • #12
Mstng93SSP said:
Just a sidenote, with an A9P you should not have changed to the 5 speed O2 harness. The computer/ecu dictates the O2 harness, not the trans. A9P uses an AOD O2 harness and an A9L uses a manual 5 speed O2 harness. You can run a 5 speed on an A9P with an Auto O2 harness with no issues.

Chris
Click to expand...

Second this. I'm actually surprised this turned out to not be why your car wouldn't start. Start voltage is directly involved in the neutral safety circuit in the auto setup, and NOT in the manual setup.
 
D

dwith66

Member
Jun 16, 2019
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Stoddard, Wisconsin
Jul 25, 2020
#13
  • Jul 25, 2020
  • #13
I'll try to clear up the confusion, I repinned the 02 harness using this information: Same harness repinned

An AOD O2 harness can be converted to a T5 O2 harness in 5 minutes.Simply unplug the O2 harness connector located under the MAF sensor in 89+(88 Cal.)5.0 mustangs.Use a small flat head to remove the red plastic insert inside the connector which locks the pins in.With a tiny flat head,bend the plastic locking tab back that holds the pin in and use a straightened paper clip or something to push the pin out.You'll notice the AOD harness has one unused pin slot and the gray rubber section does not have a hole for this unused pin.Use a small drill bit to poke a hole in this soft rubber.Now move the purple/yellow looped wire from the AOD position to the T5 position.This must be done to every AOD to T5 swap but is never mentioned in any of the popular how-to guides !!!!
 
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ZephyrEFI

Active Member
Mar 9, 2019
105
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Shakopee, MN
Jul 25, 2020
#14
  • Jul 25, 2020
  • #14
It must be done only if you go to a manual computer. It's better of you don't, if you're sticking with an auto computer.
 

Mstng93SSP

You have a nice rear end there Dave.
15 Year Member
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#15
  • Jul 25, 2020
  • #15
Yes I understand how to repin the harness, but the statement that this needs to be done on every T-5 swap is incorrect. The only reason you would do this on a T-5 swap is if you ALSO swap the A9P for a manual A9L (Which you do not need to do). My point is if you keep the A9P computer you should not repin the harness. The harness is related to the A9p or the A9L only, not which trans is physically in the car.
 
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