05 tundra intermittent no crank

I thought my battery was getting tired but I found that when it wouldn't crank, as i released the key, it would start. So this went on for a couple of weeks. I took the starter switch assembly apart and cleaned/inspected the plates, springs and contacts, it didn't change the symptoms. Jacking the shift lever around made no difference. Tapping on the starter relay made no difference. Finally it just stopped cracking altogether.
Oh btw 260k on it.
So I got a starter motor (new, not reman) and replaced it. I thought that I would make shure the the carquest starter that had to have been put in before I got the truck at 149k, was actually the culprit, before I put everything back together. With just the starter connected, I tried it and had the same deal. I swapped the starter and heater relays. Btw the solenoid never clicks. Do I need something else connected before the thing will crank? I hate to think I went through all that for the starter not to have been the problem.

 

If you havent already I'd start simple.
Check for corrosion and connection of the positive and negative terminals on the battery. Locate the other end of the negative coming from the battery and check it also.

Fuses and relays.

Then check for 12volts at the starter's power wire. Then check the ignition wire as the key is turned.

IMO, a bad relay could be the culprit. Maybe there is another relay that you haven't found that is related to the ignition/starter system.

 

Checking the other end of the chassis great idea! I will also make shure I have power at the main starter lug and the solenoid wire with the key turned. Still the strange thing is the way it started to fail, engaging when I released the key back off the start position. Naturally made me think switch, still may be. I have taken it apart twice and don't see anything wrong with it...maybe I should check that theory with an ohm meter? Thanks for the advice friend.

 

Hey Twinky,
Ok it runs! I did everything you said. I also noticed that when I set the key all the way over to start, my clock dimmed out. I started at the ignition switch with a test light and the relay signal came out of the switch but did not show up at the starter relay. I ran power to the solenoid lead on the starter and she cranked. At that point I started pulling fuses out , 3 at a time, to see if anything was pulling it down. I finally found a 30 amp in that 3rd little fuse box that was blown. So once I put everything back together ...shazam! Ok now it runs great but throws a code 345 (cam position sensor).
Both sensors read pretty close, resistance wise. Checked all connectors etc.
Btw.. I used to own a 1964 CC Super Sport.
I sold it to my father in law's good buddy for a buck, and now it's in California, probably looking brand new. Oh, I also found the Heater fuse in the fusable link assembly was blown. I haven't replaced it yet, I wouldn't think that would cause a cam sensor code?

 

The wires could be chewed up or the sensor itself could be bad. It'll cause a hard/no start issue.