Question

I have a 1996 Ford F150 5.0L V8. I'm getting the P1780 error code. o/d off light flashing on the shifter for automatic transmission.

Answer 1

P1780 Transmission control switch  / Transmission control indicator lamp

This code you can only get when you do a KOER (key on engine running ) test, and not cycling the O/D switch . during the KOER test,

Answer 2

P1780 Ford Code - Transmission Control Switch Circuit is Out of Self-Test Range
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