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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-

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

  • Thread starter Thread starter ChaseRoads
  • Start date Start date Jan 21, 2023

ChaseRoads

do I need to lube this area?
Oct 29, 2020
220
73
38
midwestern america
Jan 21, 2023
#1
  • Jan 21, 2023
  • #1
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

do I need to lube this area?
Oct 29, 2020
220
73
38
midwestern america
Jan 21, 2023
#2
  • Jan 21, 2023
  • #2
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

do I need to lube this area?
Oct 29, 2020
220
73
38
midwestern america
Jan 21, 2023
#3
  • Jan 21, 2023
  • #3
put it back in, fired right up, still getting codes 11,10,15. not sure what else to check.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,164
17,859
224
Massachusetts
Jan 22, 2023
#4
  • Jan 22, 2023
  • #4
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.
 
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