4Crawler

iTrader: (3)

Well, probably first test for voltage across the two wires that connect to the relay coil. Per the wiring diagram on my web page, the two solid black wires (at the connector) connect to one side of the relay coil and one side of the contacts. The black w/ red stripe wire is the other side of the coil. And the black w/ white stripe is the contact that runs to the starter. So see if the black wires (at the relay connector) are getting 12 volt as the ignition switch is put in the start position. If not, something is preventing that 12 volts from getting to the relay, so the relay itself may be OK. If you are getting 12 volts at the relay, then it is likely bad and would need to be replaced, either with a stock relay or you could wire in a regular headlight relay.

jungle_runner

So, unplug the relay connector and put the red lead onto one of the black wire contacts and the black lead to a ground? And then test the other black wire?

Some more photos.
1) Battery is good


2) My little testing rig I bolted the relay on one of the rubber hood stop mounts and set the meter so I could read it while I turned the key to start. I got 0.0 volts on both sides of the relay (B to W & BW-WB) the wires are a different color pass the connector.



3) I tried running power directly from the battery to the relay, I got the same result as if I turned the key to start. A *click* and a faint *squeal*


4) The starter relay wires disappear into the passenger fender. Is the next stop for these wires the ignition switch, or is there another junction somewhere I should test?


i think i'm making some progress
thanks

4Crawler

iTrader: (3)

Click/squeal is the Circuit Opening relay turning on with the key in the start position (the click) and the squeal is the fuel pressure regulator bleeding fuel back to the tank. You'll likely hear a whirring sounds back at the passenger rear wheel well, that is the fuel pump running.

If no voltage at the relay, as measured with the red meter probe on one wire and the black one to ground or to one of the relay wires that is supposed to be grounded, then this means something is preventing voltage from getting to the relay. What else? Ignition switch and/or wiring between there and the relay or between the battery and the ign. switch.

jungle_runner

I ran the tests again, this time using the battery negative post as the ground. Turning the ignition to the start position for each test.

I started by disconnecting the starter relay and I tested each of the black wires going into the connector. 11.4-11.5 volts for both.

Then I reconnected the relay and tested all 4 wires soldered to the relay. All were 11.4-11.5 volts (with clutch pressed or not, didn't make a difference).

Needs to be 12 volts coming in and going out right? So the ignition is bad or a wire coming from the ignition is bad?

How can I jump start the truck? Just to get it going. I ran power directly from the battery and the starter didn't turn, just did the same thing as turning the key but without turning the key.

jungle_runner

based on this diagram below (found here), the two black wires (pin 3 & 4) are actually connected in a loop? And the relay just gives the circuit more juice? I'm going to google relays and get some basics. Tomorrow I'm going to cut the pin 4 black wire (adjacent to the black-white wire) and run it directly to the battery. You page doesn't say what kind of fuse. 30A? Thanks

4Crawler

iTrader: (3)

Could be a ground issue then, but in any event you should see the battery voltage (whatever that is) at those relay pins under no load. If you get no volts across the relay socket then check the grounds. For a complete circuit you need power and ground. For an example (not to try, just to think about), if you touch a metal bar to the battery + terminal, nothing happens. Touch it instead to the negative terminal, again nothing happens. But touch it to + and - at the same time and you complete the circuit with dramatic results. So as you can see, you need 12 volts and ground (0 volts) at the relay coil to make it turn on. To jump start the truck, take a wire from the + terminal on the battery top the small terminal on the starter solenoid. If that does not make the starter turn, you have some other problem. Again, check the grounds. Why? The starter gets 12 volts from the battery + terminal, but guess where it gets ground from? By being bolted to the block. Block in turn should be connected back to the battery - terminal via 1 or more ground wires. If one or more of those are bad, no ground = no current flowing = no start.

4Crawler

iTrader: (3)

Yes, the two blacks are connected together. So the relay coil and the relay contacts get power from the ignition switch (via any neutral start/clutch cancel contacts). Not really sure why Toyota wired it this way as the relay really serves no purpose. The fix as described on that page makes the starter relay perform better by running the contact power to the battery. This way you bypass all the stock wiring, switches etc. that cause the big voltage drops and make the starter work better. And if you want to fuse it, use 30 amps or so, the solenoid pulls at least 20 amps by my measurements.

jungle_runner

it worked!

1) I made sure the truck was not in gear.

2) Made sure the parking brake was on good.

3) Turned the key to the 'on' position.

4) Plugged the wire into the starter side first (because I didn't want to have my hand in there with the engine starting)

5) And then put the other end of the wire onto the positive terminal of the battery... and it cranked!!!

Thanks!!!

jungle_runner

I spliced the black wire on the black-white wire side and ran it directly to the battery with a 30A inline fuse. Here are some pics, the overview and the detail.




Now I get 12.4 volts on the connector for the black wire attached to the battery, of course, but with the key turned to start, I'm still getting 11.4 coming out on the black-white wire that goes to starter. So I have to say, bad relay.

I'm going to find a stock relay at a pick-a-part yard. At least I can start the truck for now with a wire straight from the battery, thanks again for that tip.

I feel a lot more competent with electrical issues now that you've told me the basics. Thanks again for all your insight!

sexyfatkid

great thread! i've been having the same problem. just havent had time to work on it. this gives me a heads up what to look for. thanks guys.

jungle_runner

Hey 4Crawler, the black w/ white stripe wire runs to the small plastic clip on the starter right? I figured that if I touched a battery wire directly to that wire instead of reaching into the wheel well for the connector that the small plastic clip goes into, that the starter would turn.

But it didn't. Is there something in between the black w/ white stripe wire before it reaches the starter? Or could the wire be bad somewhere? I may have to slit all that electrical tape that holds the wires together and trace the black w/ white stripe wire all the way to the starter.

Thanks again!

4Crawler

iTrader: (3)

Likely that wire runs to the solenoid. You could see if it is the same color insulation on both ends. Could be there is corrosion of the conductor up inside the insulation at one end or the other.

jungle_runner

turns out that the wire isn't the same color, it's yellow and black, and as i've been pulling apart the wiring harness, this yellow and black wire is appearing all over the place, even in the speakers ... so it's not the stock wire, it's the wire mr. previous owner used ... grrr ... i've got to figure out what he was trying to do and why he did it ... this may take a little while

the yellow and black wire (green path in photo) goes into the cab, and the starter relay wires (blue path in photo) go into the side fender

... and they both seem to go to the ECU behind the passenger side kick-panel


know where i can find the complete wiring harness diagram online? also, the vacuum lines diagram? (i've labeled with a marker, but i think some are wrong to begin with)

jungle_runner

confirmed that the yellow/black wire comes in behind the ecu and then connects to a connector and that group seems to lead to the driver's side.



i have found a few connectors here and there unplugged! and a really poor wiring job tapping into the ignition ... mr. previous owner has left a nice mess for me

but if i get through this ... i've learn a lot eh

jungle_runner

ok, found two things that are causing the problem

1) the plastic connector that clips onto the starter (from the ignition switch) is not making good contact. this is easily fixed by getting a new connector.

2) i cut the ignition wire where it comes into the engine bay and placed the probe of the volt meter on the wire. when the key is in the ON position i get 12 volts, when the key is turned to START the voltage drops to 11 volts. i don't know what this means.

any suggestions?

thanks

jungle_runner

so i was at the stealership getting a new radiator cap and i mentioned the problem i was having with the starter ... the parts counterperson said that it's probably a bad wire in between the ignition switch and the starter and that instead of searching for the bad wire i could just add a relay on the ignition wire in the engine bay (or i could sell my truck to him, ha, no way i told him)

so i added the relay along the ignition line and now the starter turns when the key is in the ON position! and START position! ... so now it's "starter happy"

i went to a lot of sites about wiring a relay so i'm sure i've got the terminals right:
86 - switch
85 - ground
30 - battery (with inline fuse)
87 - device being powered (starter)



here are some good links:
http://www.therangerstation.com/tech...ry/relays.html
http://www.thisoldtractor.com/gtbend...m_-_relays.htm

so based on what i've now learned about the way relays work, the ON position closes the switch and sends 12+ volts to the starter ... the parts guy didn't know what he was talking about ... looks like i'm going to have to pull the dash apart and test (and replace) the ignition wire

wheatus

i am having the same problem and wondered if you ever got it sorted out

jungle_runner

there was an alarm system installed and the wiring was different than the books ... a mechanic took one of the wires than runs from the relay and ran it straight to the starter ... starts fine now

yotadude85

you know... i have had this same problem it sounds like. it started only when it was below freezing. thought that maybe the starter has seen some water which is likely from what we use the truck for. though it was a new starter we replaced it again, bought a new battery and the alternator just because. we later found after taking the relay apart like you did that it was the problem. there was some water and rust inside the metal cap. cleaned it out and it worked great for about three to four weeks. Now it wont start at all. Same EXACT symtoms as yours. it will push start and fire right up but the starter will not turn over. clutch in or out clutch cancel button pushed... doesnt matter. sounds almost like a bad connection but i have been all through the wiring several times. click and a sound almost like the starter is trying to engage(sounds like a damn near dead battery) My truck still sits in the driveway broken hopefully this helped you? maybe someone can help me because i cant find a new relay anywhere!!! dont want to modify for aftermarket relay...

yotadude85

mine has an aftermarket alarm aswell that has been disconnected i think? which wire are you talking about? maybe the relay isnt my problem...