I have a 2000 3rd gen and we pulled the engine to install the timing belt kit with water pump, torque convert seal, new valve cover gaskets, oil pan gasket, radiator and hoses. We reinstalled the engine and hooked it all back up and now we are getting nothing. Battery shows good from the charger. Light work, windshield wipers work, horn blow, radio comes on, but no starter turns over at all. We have traced down the grounds again. Checked and rechecked them. It has the factory alarm no aftermarket on it. I am lost as I thought it was ready to go. I followed the timing install to the T and it lined up perfectly with the Toyota kit. We can turn the key and hear what sounds like fuel pump but no starter to engage. It was running great before we pulled the motor. I have looked at the forums, googled till my fingers hurt and I feel silly. I have built motors before and thought it was starter but it looked newer.

Double check the starter relay first. Do you here a "click" when you turn the key to start it? If you've got a power probe, you can give it power to the connector on the starter to see if you get a click (red circle). You could even turn the ignition to the "On" position, and power that plug and see if it turns over and starts up.

Also, could be the park/neutral position switch (red arrow)

Here's a diagram to get you started:

this may not be the right next step but when mine didnt start i tried jumping the starter solenoid to see make sure the starter would function. Both were working and it ended up being the stupid aftermarket alarm but thats where i started.

How do you jump the starter solenoid?

Get a jumper cable and attach it to the bolt that has the starter wire coming from the battery and then attach the other end to the positive post on the battery. You'll still need to the try and turn it over with the key, so if your starter relay is bad in the engine bay fuse panel this won't help.

If it then starts with this method, you have a bad starter wire coming from the battery to the starter.

We have power from the test light we used at the starter. We noticed that when we turn the key the dash clock goes out. Not sure if that’s normal? If we hook the site and it starts will it continue to spin the starter?

Sounds to me like a bad starter wire.

It won't. You'll still have to turn the key over in order to engage the starter relay, which then engages the starter solenoid on the starter itself. What you are essentially doing is bypassing the starter wire that goes from the battery to the starter to test if it's bad. Basically bypassing the Blue-Black (B-L) wire in the diagram I posted (lower left-hand corner of image).

1st thing i would do is go back and make sure all the wiring connectors r fully seated into their assigned locations... especially at the ECU. While ur doing said make sure all ur grounds r good, get ur hands on a volt meter if u dont have 1.

Do you have a Factory Service Manual? There's a great diagnostic check list you can go down that should get your problem solved. It's most certainly an issue with the starter. The dimming lights when trying to crank screams starter wire to me. PM me if you need a copy of the FSM.

Ran the wire from starter to battery and still nothing. Checked the ECU wires again. Put in a new battery and still nothing. I’m not getting even a click click click on starter.

If you go into the fuse panel in the engine bay, locate the starter relay (purple relay in my picture) and try connecting a wire from pin 5 and 3. This should cause the solenoid to click and then turn the starter over. This is effectively bypassing the ignition switches and all the stuff upstream in my previous wiring diagram. If you have the key turned to the "On" position, and your starter is good, it should fire up. This would indicate a bad starter relay if it indeed turns over/starts up.

Just so you or anyone else understands what we're doing (not that you don't), it sounds like we've tested the starter wire by using jumper cables to bypass that wire (circled in red). It's something that caused me and several others issues. Looks like this is not your culprit:



Now, we're going to test if the starter relay is bad by circumventing it with a jumper wire.

We put a loop wire into the 5 slot and into the 3 slot to create a connection between them and tried the key still nothing... not even a click. Could the door lock unlock feature be stopping it? I still have the hood off as well.

This is starting to sound like potentially a bad starter or bad ground. At this point I would remove the starter and bench test it to make sure everything is working. Do you have a powerprobe? If not, you'll need some wires and jumper cables. It might be worth the time to pull your battery out to use it on the bench to the test with as well.

You're going to test whether the solenoid plunger engages when providing power to the plug and then whether the starter turns when providing power to the starter motor.

Here's a link with some more troubleshooting: Toyota/Chrysler/Mitsubishi - Nippon Denso Starter Solenoid Repair

Also, that wiring diagram for the starting and ignition is for a 2002, so it might not be pin 3 and 5. When you use the jumper wire you will hear the click of the solenoid and the starter turning the motor over if everything is in order.

@TheDurk