XJ Transmission swap - Wont go into gear and grinds when returning to park
 

HAD: 2000 Sport 4.0L with AW4 with a cracked head.

SWAPPED: 2001 Classic 4.0L (25kmile rebuild) with AW4. Used his engine wire harness

We chose to change engine and trans together (never decoupled) and it went without issue. After replacing the ASD relay engine starts perfect, but we have 2 Problems:

*NO Headlights
*NO Trans engagement

we tried full fluids, swapped PCM, ECM, TCM. some combos gave a P1387 code, some shut the engine off. when we have my 3 original computers we get no codes, but also no headlights (have fog lights and replaced both headlights) and no trans engagement, just grinding when going into park.

ive noticed the donor Jeep has 2 more relays in its fuse box than mine,

I’m out of ideas. Can anyone help here ? Thanks in advance and yes it’s my first post so I hope I’ve provided good info and etiquette ?

Dumb question, but you're sure the xfer case isn't in neutral? That will cause grinding trying to go back into park.

would cause both issues. My first thought.