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Corbet
07-19-2009, 02:26 PM
OK, today finally had some more time to continue trouble shooting my no start issue which began back at CM09, see thread:

http://www.risingsun4x4club.org/forum2/showthread.php?t=9822

Then after a few weeks back home I got a check engine light indicating a camshaft position sensor problem. See thread:

http://www.risingsun4x4club.org/forum2/showthread.php?t=10053

So today I replaced the wiring harness that failed in Moab. I upgraded it significantly as I plan to upgrade the alternator in the future. Pic below.

jettaglxdriver
07-19-2009, 02:30 PM
That looks pretty good. Is that splice with the bolt in it insulated from shorting out?

Corbet
07-19-2009, 02:32 PM
I also replaced the AM1 & AM2 fusible links. Inspected the harness behind the EGR, see pic below.

After reassembling it still will not start. I do not have a check engine light with the ignition hot. So I know my ECM is no longer getting power. It was before I started replacing the section of the harness that failed. However I do have headlights and HVAC controls working properly, which did not in Moab, when this all started.

Corbet
07-19-2009, 02:35 PM
That looks pretty good. Is that splice with the bolt in it insulated from shorting out?

Yes, I recovered the whole harness with the plastic corrugated OEM crap then wrapped it with some insulating shrink tape stuff. But I did not take a pic of that. The bolted connection is where the OEM harness had a simple crimp connection of 3 wires. Pic below. I think my 2 tinned lugs with a bolt is a better solution but I could be wrong.

Hants
07-19-2009, 07:27 PM
That's a bummer, Corbet. I don't have any direct knowledge to contribute. :(

There was a thread on Mud a while ago on a similar topic. IIRC, it had to do with different critical circuits in that harness, and a corroded connection in it or at the alternator that was causing lots of grief. May have been started by Onur (Beno)?

Another suggestion: There's a very old thread on Mud that discusses the minimum circuits necessary to get a running engine. IIRC, there are only 2 or 3. May point you in a direction.

Yet another: The threads on Mud regarding the upgraded Tundra alternator brackets. Lots of wiring tips there for this harness.

Corbet
07-20-2009, 07:59 AM
There was a thread on Mud a while ago on a similar topic. IIRC, it had to do with different critical circuits in that harness, and a corroded connection in it or at the alternator that was causing lots of grief. May have been started by Onur (Beno)?

Another suggestion: There's a very old thread on Mud that discusses the minimum circuits necessary to get a running engine. IIRC, there are only 2 or 3. May point you in a direction.

Yet another: The threads on Mud regarding the upgraded Tundra alternator brackets. Lots of wiring tips there for this harness.

Thanks, I've read most all of those. I'll probably have to break out my electrical FSM/voltmeter and start searching for a short. I was hoping someone would have some experience here and point me in a direction of a common problem area.

Corbet
07-23-2009, 07:45 AM
From Robbie (Powderpig)

"You state that you have no power to the computer. Have you run a hot wire to the computer(fuzed some way). ? If not I would try this to make sure the computer is not screwed up. If it runs with a hot wire to the computer then you will know that it will run and you can go backwards from there. The EWD I have shows direct power from the EFI fuse to the computer. So If the hot wire works, and you have power after the fuse, I would then subsitute a hot wire, instead of trying to find the break in the wire at this time. If it still does not work, then you have a different problem(Safety netural switch, problem with computer, some other input not allow you to start)"

I have power under the hood at the 15amp EFI bladed fuse. Will try a hot wire direct to computer from there. :thumb:

corsair23
07-23-2009, 11:35 AM
Corbet,

Does the 80 try to start at all, or is it a "turn the key to start and nadda" type thing? Reason I ask is that Romer ran into the no start issue on Sarah's LX and it was the neutral safety switch or whatever it is called. Robbie's comments above sparked that memory 'cuz that was one of the things I checked on the 80 when it wouldn't start...In my case though the no start issue turned out to be a previously fubarred starter contact R&R on my part :hill:

Corbet
07-23-2009, 12:11 PM
cranks but no start. No CE light at ignition hot indicating no power to computer and thus no fuel or spark at engine. Need to jump power to computer as Robbie instructed. Probably no time until weekend to do so.

TIMZTOY
07-23-2009, 05:35 PM
never opened the hood of a fj80 so im not farmilare with the setup.
but if its a distributor setup. most cars with this simmiler problem end up being a failed ignition controle moduel. (some mounted external on fender, some inside the distrbuitor).. might also be "EFI relay" if equipted which controles fuel and spark. also seen pick-up coils fail regularlly... im kinda just shooting in the dark since i dont know what type of fuel/ignition system the fj's use im assuming distrbuitor and coil with some electric sensors. :dunno:

Corbet
07-27-2009, 01:01 PM
I'm running again but not 100%.

Found a bad connection near the distributor today and got power back to the computer. Turn key and start, instant stall. Would run with foot on throttle. Once warmed up I"m good. No codes yet

Thoughts?

treerootCO
07-27-2009, 02:05 PM
ECU might need time to learn how to run....my 80 would not idle when the MAF sensor was messed with. Once fixed, I had to drive about 10 min before it figured it out and would idle.

corsair23
07-27-2009, 03:43 PM
I'm with Mike as a starting point...Something like 3-5 start cycles or something for the ECU to "relearn" after it has lost power for whatever reason...Although I would think it would still run, just not idle very well. That's been my experience every time I disconnect the battery for some reason.

Corbet
07-27-2009, 04:15 PM
forgot about that :o with any luck I'm cured. Probably will not know until tomorrow morning's cool start.

Corbet
07-28-2009, 09:09 AM
This mornings drive into work went perfectly. Cold start with smooth idle. No codes. Looks like I'm back on the road again.

Thanks to everyone who helped me out, especially Robbie.

powderpig
07-28-2009, 10:50 AM
I still would replace the wire that seems stiff or brittle under the coating.
Robbie

corsair23
07-28-2009, 11:28 AM
Awesome Corbet :thumb:

I dedicate my 4000th post to you :D - You kept with it and beat it

Corbet
07-28-2009, 02:55 PM
I still would replace the wire that seems stiff or brittle under the coating.
Robbie

That's my plan