If you turn the dash light rheostat, which is part of the headlight switch, all the way to the left it should turn on the under-dash light.
Sorry to not answer before, but I've been changing my T-stat. That stuff they used to seal the housing was some good stuff!
Yeah, I found the courtesy light the first day. But mine is unfastened and stuck up by the heater! It's no good unless you want to see the tips of your shoes!
I'm looking for a dome light. I'll probably just wire it in to that courtesy light wire.
And rizzo I agree that the heater is plumbed before the T-stat . But if the T-stat is stuck open, the water won't be warm enough to give out any heat in the cab. Even tho the return hose felt warm the other night, it wasn't HOT. And looking back, I seem to remember that with a properly working system, the hose would have been hot.
I got the T-stat installed, but when I started it, there was a leak. I reinstalled it with more permatex black on it and I will try it again tomorrow. I'm outta time today and have to go to work.
And tomorrow we are going to preview some trucks at Drexel Gardens. MAYBE I will have time before work to try the T-stat.