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Tundra Starting Issue

My '01 Tundra failed to start in a parking lot the other day and I am at a loss as to the problem. Battery is fine, fuses all check out, starter relay works on the bench. I was able to get home by pulling the starter relay, turning the on the key and using a wire to jump from the battery to the #3 side of the relay connection. As far as I can figure the # 5 side should be hot all the time, but it isn’t. I pulled the fuse block and installed a jumper from the fog light fuse to #5, but now when I plug in the relay the engine cranks. I tested the relay again and have no continuity without energizing poles 1 & 2 (and full connection between 3 & 5 when 1 & 2 are energized. So now I can still start by jumping from a hot to pole 3, but the relay woring on the bench and being a direct connection when it is plugged in has me baffled. Oh, and there is no current to 1 & 2 without turning the key.

It sounds like the relay is ok to me. It is working like it should be from what you say. Looking at some data it shows the relay coil leads are 1 and 2. Lead 1 is energized via the ignition switch when the key is ON or in the START position and lead 2 is the controlled return side of the relay coil. Pin 3 is the switched lead that ties to the solenoid and pin 5 is also supplied power when the key is in the ON or START position. Pins 5 and 3 are connected together when the relay is energized and voltage is supplied to the solenoid. If pins 1 and 5 don’t have power going to them with the key in the START position then there is a wiring problem to them, the ignition switch is bad, or there is a bad fuse.