Crazy shifting controlled by headlights

[Hartswelding]

Ok so my 95 f350 psd auto trans works great.. Shifts through all the gears fine. If I turn my headlights on things go crazy. It begins to shift in and out of overdrive. The cruise control stops working too. No visible warning lights either. I replaced the alternator but that didn't change anything. I am stumped can you guys give me some ideas? Any help would be greatly appreciated

[1Dieselman]

Does it do it on both high and low beam? I'm thinking that the muli function switch is messing up.

[Hartswelding]

i know for sure that it does it in low beams, not sure about the high beams but i will find out really quick.

[Hartswelding]

Yes it does it in Low beams and High beams

[1Dieselman]

Can't guarantee that it is the problem but the multi function switch can do some really strange things when it screws up. Other than that check grounds and wiring see if something is loose or chaffed. With the headlights on what does your voltage show?

[1995TSstroker]

Most likely your switch


Sent from my Autoguide iPhone app

[Hartswelding]

I hate to sound ignorant but what is a "multi function" switch and where is it located?

[1Dieselman]

It is your turn signal, high low beam, wiper switch.

[vegasjeep]

This is almost exactly what the truck I just bought was doing. It took out the ECM shortly after starting doing it. It stemmed from chaffed wires in the column

[troykimber]

yup, the wiring in the column could be the issue. i have also seen it do wierd nonsense. that and the multi-switch would be u're best bet. or just don't drive with the lights on.......