Join Date: Sep 2008
Location: Fruitland Park,Florida
According to service manual, dtc 59 may cause tcc not to apply properly.
Dtc 73 causes full line pressure & harsh shifts.
83 is for manual trans only.
90 will cause no tcc lock up & no 4th gear in hot mode.
For all these codes, not only check the sensor itself. But also check, wiring, connectors, grounds, etc. Use the 94 or 95 service manual to help you. Since I've never used or worked on a stand alone harness, I can't say how well wiring, connectors, & grounds will match up with factory wiring.
Hopefully, the stand alone harness came with wiring diagrams.