The below post was from Jrichker on May 27, 2014 in a thread. If I have an A9L and the 02 harness wired properly, maybe I'll be good to go.
The trace inside the computer burns up for 2 reasons:
1.) When someone dumped the codes, they used the brown connector instead of the gray one to dump the codes. The brown connector is for the under hood light and has 12 volts on it, this burns up the trace inside the computer.
2.) Auto trans O2 sensor harness was used with an A9L computer.
O2 Sensor harness interchange and modification
Originally Posted by 302EFI
Revised 16-Oct-2011 to add O2 sensor harness warnings
The wires for the 02's and low oil did not change throughout the years, they are all in the same place.
The main ones you need to worry about are (on the harness end (ECU) that plugs into the 02 plug) is:
\- 1. Lightblue / yellow
- 2. White / Purple
- 3. Purple / Yellow
The White/Purple & Purple/Yellow gets looped for a automatic ECU
The Purple/Yellow & Lightblue/Yellow for a manual ECU
See
http://forums.corral.net/forums/gen...manual-auto-differences-year-differences.html for more O2 sensor wiring harness info
Basic premise to use with transmission swaps:
Only run a 5 speed trans O2 harness with an A9L. Do not run an Auto O2 sensor harness with an A9L. Doing so will damage the computer’s internal signal ground.
Only run an Auto trans O2 sensor harness with an A9P in a car that has an Auto trans. Using a 5 speed trans O2 sensor harness with an Auto trans will cause no crank problems. There has been some debate about the no crank problem,and I haven't personally checked it out.
See http://www.stangnet.com/mustang-forums/749974-computer-issue.html#post7490537 for Joel5.0’s fix to the computer internal signal ground.
90 model year harness only works with 90 model cars without inspection/rework.
The 4 cylinder O2 harness uses 4 wire O2 sensors. It probably won’t work correctly without modifying it.