Truck: 86 22RE, low mileage (108,000)

History and Main Problem: I was replacing a bulb today in the instrument panel (on this model that means removing the whole cluster to get to it) and I forgot to disconnect the battery terminal before doing so. I didn't notice any sparks or smell anything when working on it, but when I put everything back together, the lights on the dash would come on, I'd turn the key, hear a click from the relay but nothing would happen. I have had no issues prior to attempting to replace this bulb.

Details: Fuses and fusible links are all fine (unless there are some I'm missing. I checked the box just rear of the battery and the fusebox in the kick panel on the drivers side. Battery water levels are good, and it reads 12.4 volts DC at rest, and 12.0 volts DC with lights on. Jumping the battery did not work. I ran out of daylight but was thinking I'd check the starter with my voltmeter tomorrow. About 6 months ago I replaced the copper tabs in the starter, as they were worn down and have had no trouble since.

Any ideas what's going on? Could I have ruined anything significant wiring wise by failing to disconnect the battery post?

Thanks.

 

A problem well-stated is almost solved.
Good job letting us know what you see, hear, smell, and indicating model-year-engine, but transmission and trim also matter. Please put that in you signature.
However, you need t provide exact details because we may be thousand of miles away.
You turned the key to what position?
Exactly which relay and where clicks?

Good job replacing the contacts.

All points between battery and pins 4 and 8 of IGN switch should have 12V when good battery is connected well. IGN PIns 1,2,3 and 7 should have 12V when you turn IGN switch respective positions.

 

Rad4Runner,

My apologies for the really delayed reply. Thank you for the detailed and careful response! Also, thanks for the reminder about extra details in my signature. What do you mean exactly by "trim"? Would that refer to something like "SR5"?

Everything is working again, and fortunately without any significant repairs. After some mysterious points when it started up just fine I decided to disconnect the starter relay, and positive connection from ignition switch to starter and clean both of them. Cleaning the relay did not work, but cleaning and reconnecting the ignition switch to starter wire seemed to fix things. I did recently have a moment when it wouldn't start, but I got out and fiddled that little wire and it's been working since. Hopefully that was the issue, and I won't be running back here for further help.

 

Ray, you Google photo isn't showing up again not sure if that is my end your end or Google problems...

Op, please state or show us which "little wire" you manipulated.

Manipulating plug connectors can vastly alter how they function(moving a plug functions sort of like cleaning the terminal). In this case it was likely either the FL (fusible link) to distribution box or the ignition switch wires.

Bright shiny metal on both ends and silicone grease to protect from oxidization.

 

Click no crank even with brand-new solenoid contacts, intermittent are symptoms of absence of starter relay OR one that was wired wrong at the factory. This problem is common among first-gens and some second gens...
Install a starter relay IF absent for approx $30. Rewire the starter relay IF present for about $11 here.

Yes, DLX or SR5; it may tell us what features/circuits your truck has or does not have.

Sorry, I might have deleted / moved the google photo because I could not find it anymore.... Editing above post with new schematic...