What’s that?!? (Updated edition!)

[nvrenuf]

Those colors ,orange & white,were used on the dome & courtesy lamps and maybe the seat belt buzzer/light on some square bodies..but it could power something else too..

Yeah, I saw that the under dash courtesy lamp and door pin switches used orange and white, I just can’t figure out why it would be constant 12v.

 

[Bent77]

Yeah, I saw that the under dash courtesy lamp and door pin switches used orange and white, I just can’t figure out why it would be constant 12v.

Feed wire to the door switch. Door switch is normally open when door is closed, circuit adds the power once door is opened and goes to the lamp

 

[diesel4me]

I think the door jamb button grounds the circuit to light the lamps ..

 

[Bent77]

I think the door jamb button grounds the circuit to light the lamps ..

Think you're right. Pondered that after I posted.

Thus the door switch grounds to close the circuit, lamp would be always hot

 

[nvrenuf]

Makes sense, both pin switches are jacked. I’ll be fixing those sooner than planned. Thanks!

Any ideas about the gray box behind the cluster?

 

[diesel4me]

Nothing I've seen on my older square bodies--what year is yours ?..1980's ?...might be a wiper delay module or a EST spark module ..

 

[nvrenuf]

It’s a 91. The wiper delay is on the underside of the column so it’s not that. I’ll keep looking.

 

[diesel4me]

EST was only used a few years around 81-84,so its not that either..
Someone else here will know,I have never had a square body newer than an '85 so far..
I have come across a strange printed circuit board on a harness near the radio on my '82 diesel pickup,have no clue what it was for,maybe the factory dual tank setup I had that was butchered when I got it,its been deleted now..may have been for the fuel gauge ?..

 

[frankin5]

Might the fuel module, not sure what it does, full of Diodes,