A temporary fix I’d try is turn the key-on, engine off shift to neatrual. Start the truck and then you can go into gear from there. Have you parked the truck on a lot of inclines or has it been relatively flat areas?
In my opinion it is possible that while your brake lights and switches work the interlock solenoid could be gumming up. Ive also read that some trucks and cars have an interlock fuse that you could pull.
Nope. Your best bet is to get a Hayne’s manual, because they are cheap, and should cover the part you are looking for. I also recently purchased an entire Factory Service Manual in digital form for my ’99 Toyota Rav4. It was $8. I don’t remember the site I got it from, but I just googled it, and couldn’t pass on the deal.
Yeah, ebay might have something cheap also… either a new/used haynes of a CD.
Have you checked out the AllData DIY software?
It’s pretty cheap and you can get it at autozone.
I’m voting brake light switch, I think it has separate contacts for the interlock. The only way to know for sure is to get your hands on a wiring diagram for that circuit, don’t just put an interlock on it and hope you fix it see if it’s getting the signal it’s suppose to when you depress the brake pedal and if it doesn’t you can then track down the cause and the reason it’s not working and then repair what’s broken.