Auto Transmission shifting problems w-no power/winter/checkTran indicator lights

[3dlights]

I have a 95 Passport that I have just rebuilt the engine. After getting everything back together, the transmission seems to be stuck in winter mode. I did not notice this problem before the engine rebuild. I purchased the vehicle knowing it needed repairs. It has turned out to be a bigger project than expected....

I replaced the transmission filter and fluid after the rebuild as a precaution.

It shifts and runs fine when I manually shift the transmission.

I have no lights on the Transmission Indicator Panel. The owners manual says the A/T Oil light should turn on when the ignition switch is turned on and then go out after a few seconds. I have no lights on this panel at all - ever. I have checked the winter and power switches electrically and they seem to be fine, but pressing them has no effect on the transmission mode, nor do I get any indications on the panel as previously mentioned.

Voltage checks at 13.94 VDC when the engine is running and 12.48 VDC when not running. I have no voltage drops when I measure the voltage from the positive battery terminal to the engine block, which would indicate my grounds are ok.

All fuses on the inside drivers area (lower left side of steering wheel) and inside passenger fender-engine compartment check good. I cannot find any defective wiring or connectors. No codes are present on the ECM. Disconnecting the battery for 30 seconds does nothing. As suggested in another post, I also pressed the POWER and WINTER buttons within 3 seconds of starting to read the ECM codes -- No Change.

I did get an antilock brake light for a few minutes the other night. Disconnecting the battery has cleared it, and it has not returned yet.

Where is the Transmission Control Module-TCM located and is there a way to check it? Can I read codes from it?

Any suggestions why I don't have any lights on the transmission indicator panel?

What causes the transmission to go into this mode?

Are there any online troubleshooting manuals or detailed wiring diagrams available (free or otherwise)?

Any help would be greatly appreciated!!

David

[3dlights]

UPDATE:
Ok.... I'll tell you what I found. After locating a good electrical schematic from a mechanic friend of mine, I found a small ground wire not connected "ahead of the starter". After connecting it, all is well. Transmission indicator lights work as they should and the transmission shifts beautifully.

Thanks,

David

[FL 3.2L]

I hope your shop knows how to check the fluid level properly (running and in neutral).