chasing a code 15c issue. Is this pin 1?

[ChaseRoads]

car info. 91 GT vert. Factory 5.0 auto. Just finished a tkx swap.

Factory A9P ecu was out of the car sitting on a bench for maybe 3 weeks. Replacement A9L was install, found to be bad, then removed.

O2 harness was repined for new ecu, then returned to factory configuration. a9p was put back into the car.

since reinstall, car had a 30 minute test drive, then an 1 hour, 70 mile test drive, and a 10 minute drive to taco bell because the mexican pizza is back..

Decided I would pull the codes to make sure non were there. Got 11, 10, and 15c.

Is this the correct place to check for constant 12V?

if so, what else can I check to confirm my kam is shot?

Will having the ecu out clear codes? or do i have to do the hooked up, pull ground and turn on headlights thing?

 

[ChaseRoads]

Checked resistance from 40-60-46 and everything is connected and showing low resistance. Gonna hook it back up and make sure the 1 pin fully seats.

 

[ChaseRoads]

put it back in, fired right up, still getting codes 11,10,15. not sure what else to check.

 

[Mustang5L5]

If you hook up power and fire it up right away and pull codes, you always get a code 15. You need a few on/off cycles with power still connexted. In fact. Do a few cycles, then erase codes without pulling the ECU out, then do another few cycles and pull the codes.

To erase the codes without disconnecting the ECU, just remove the jumper wire while the cel is blinking, or turn the code reader off/disconnect while it’s reading out the codes. That will erase them.