2000 J-shift 4WD troubleshooting next steps

[brokedownwallet]

[MENTION=10169]TheDurk[/MENTION] not to bother you with another 4WD post but I'm pretty sure I've read all that I could find.

2000 SR5 with 5-spd manual. 4WD worked a month ago but I haven't been able to figure it out as I've been working on larger ticket items. 4WD lights don't come on at all

VSVs and ADD check out good. I tried to get under the car with a multimeter and paperclip to close the circuits on the receiving connectors and check the two position sensors. If only have 2 switches because of the MT.

Shorting the passenger side harness with a paperclip switches the VSV, shorting drivers' side doesn't. I can't reach the switch with the multimeter to check that though. Weirdly enough, shorting the driver side with the same paperclip doesn't switch the VSV and I already tried cleaning it out earlier in my diagnosis process. Has anyone seen a receiving wiring harness ever go bad? It's pretty crusty in shape and I'm not sure what's going on with it. If the harness failure is the issue, could it prevent the light from engaging on the dash?

Currently neither 4HI or 4LO switch the VSV. Replace both harness and switches? I also need 4WD soon as I'll be driving up to the mountains, I heard some people wired a manual bypass for the ADD, any idea how best to do this? If I'm driving up tomorrow, could i theoretically swap the ADD vacuum hoses and leave it engaged and then just switch between 2hi and 4hi from the jshifter? Or does the tcase need to engage the driveshaft before the front diff?

 

[2TH4IST]

There is also a switch on the add actuator. Similar as t-case but doesn't have a harness pigtail. Should be 3 switches total IIRC, 4 if you have a e-locker. I'm not infront of my diagram, so that's all I can help you with now.

I have the similar issue, I have the switches sitting in a box waiting to be installed.

 

[JustTroItIn]

Here's a pretty good thread with diagrams. SOLVED - Help troubleshooting 4WD issue for '00 with j-shifter

 

[MT4runner1980]

I just finally fixed mine, so I have a lot of experience with the entire system now lol.

You don’t have 4hi or low? It doesn’t shift or the lights are flashing on the dash, it shifts but doesn’t engage? You need to pull the 4wd switches through out the vehicle, don’t climb under there and try to test them while installed. They’re 27mm I believe. You have 2 on your TC actuator, 3 on top of the TC(2 on the drivers side and 1 passenger), another on the front diff actuator. Check for continuity on them, simple test, replace them if they’re bad. If they are still good clean them and put them back.

I replaced the switch on the TC actuator, replaced the front diff switch, and then the entire front diff actuator as it wasn’t holding vacuum. It shifted in and out of 4wd much better but the dash lights were still flashing and it would intermittently engage in 4wd.

I took my vsv valve off, sprayed out the connections, blew air through both, then put it all back together. 4wd is working perfectly now!

I had bought the other 3 TC switches but didn’t install them, they’re a nightmare to get to unless you have a body lift. There’s diagrams out there that explain what each switch actually does which is good to learn. I also jumped my TC actuator with a battery to manually ensure the actuator was working.

Hope my troubleshooting experience helps in some way.

 

[MT4runner1980]

Also the vsv switch is discontinued from Toyota, but there’s posts out there on how to buy replacements from other Toyota vehicles that are identical and will work if you need to replace them.

 

[TheDurk]

[MENTION=10169]TheDurk[/MENTION] not to bother you with another 4WD post but I'm pretty sure I've read all that I could find.

2000 SR5 with 5-spd manual. 4WD worked a month ago but I haven't been able to figure it out as I've been working on larger ticket items. 4WD lights don't come on at all

VSVs and ADD check out good. I tried to get under the car with a multimeter and paperclip to close the circuits on the receiving connectors and check the two position sensors. If only have 2 switches because of the MT.

Shorting the passenger side harness with a paperclip switches the VSV, shorting drivers' side doesn't. I can't reach the switch with the multimeter to check that though. Weirdly enough, shorting the driver side with the same paperclip doesn't switch the VSV and I already tried cleaning it out earlier in my diagnosis process. Has anyone seen a receiving wiring harness ever go bad? It's pretty crusty in shape and I'm not sure what's going on with it. If the harness failure is the issue, could it prevent the light from engaging on the dash?

Currently neither 4HI or 4LO switch the VSV. Replace both harness and switches? I also need 4WD soon as I'll be driving up to the mountains, I heard some people wira manual bypass for the ADD, any idea how best to do this? If I'm driving up tomorrow, could i theoretically swap the ADD vacuum hoses and leave it engaged and then just switch between 2hi and 4hi from the jshifter? Or does the tcase need to engage the driveshaft before the front diff?

You got some good advice on the switches in posts above. You can indeed leave the hoses switched, but in 2H the front fdriveshaft will be spinning and that should be a very short term solution. I am in fact running a bypass switch right now as I don’t want to fix the switch until warmer weather. I am out of the country so I dont have access to my EWDs. I just hitched a spst switch to the 4wd relay which for MTs like ours is in the pax footwell just above the carpet on the right. If I had my EWD I could tell you which wires to short, but I don’t.

 

[brokedownwallet]

You got some good advice on the switches in posts above. You can indeed leave the hoses switched, but in 2H the front fdriveshaft will be spinning and that should be a very short term solution. I am in fact running a bypass switch right now as I don’t want to fix the switch until warmer weather. I am out of the country so I dont have access to my EWDs. I just hitched a spst switch to the 4wd relay which for MTs like ours is in the pax footwell just above the carpet on the right. If I had my EWD I could tell you which wires to short, but I don’t.

I appreciate the response; I ended up keeping the hoses switched for a short term solution which ended up being enough for the couple days I was in CO. I'm finally getting around to trying to fix things up before the summer road trip and I think I'm going to try and wire a bypass switch since I have other more pressing maintenance items and don't feel like chasing the electrical gremlins of wiring. I'd appreciate any insight or instruction on wiring the bypass switch, I think at this point it's really a measure of how much chasing down the problem is worth and I'm not two bothered with a two part 4wd solution.

 

[brokedownwallet]

I just finally fixed mine, so I have a lot of experience with the entire system now lol.

You don’t have 4hi or low? It doesn’t shift or the lights are flashing on the dash, it shifts but doesn’t engage? You need to pull the 4wd switches through out the vehicle, don’t climb under there and try to test them while installed. They’re 27mm I believe. You have 2 on your TC actuator, 3 on top of the TC(2 on the drivers side and 1 passenger), another on the front diff actuator. Check for continuity on them, simple test, replace them if they’re bad. If they are still good clean them and put them back.

I replaced the switch on the TC actuator, replaced the front diff switch, and then the entire front diff actuator as it wasn’t holding vacuum. It shifted in and out of 4wd much better but the dash lights were still flashing and it would intermittently engage in 4wd.


I took my vsv valve off, sprayed out the connections, blew air through both, then put it all back together. 4wd is working perfectly now!

I had bought the other 3 TC switches but didn’t install them, they’re a nightmare to get to unless you have a body lift. There’s diagrams out there that explain what each switch actually does which is good to learn. I also jumped my TC actuator with a battery to manually ensure the actuator was working.

Hope my troubleshooting experience helps in some way.

yup no 4-hi or low, the front diff actuator works since swapping the vacuum hoses but leaving the tcase shifter in 2wd locks the front driveshaft. I'll test the switches further but neither 4hi or low puts on the dash light and I think one of the receiving harnesses is bad since shorting only one of the receivers switches the vacuum hose. Maybe both have to be shorted? I should try and get my hands on a 4wd EWD and trying to understand it next but electrical isn't my strong suit.

 

[TheDurk]

yup no 4-hi or low, the front diff actuator works since swapping the vacuum hoses but leaving the tcase shifter in 2wd locks the front driveshaft. I'll test the switches further but neither 4hi or low puts on the dash light and I think one of the receiving harnesses is bad since shorting only one of the receivers switches the vacuum hose. Maybe both have to be shorted? I should try and get my hands on a 4wd EWD and trying to understand it next but electrical isn't my strong suit.

Only one of the switches governs the front diff. The other sends a signal to Engine Control Module to do something but I don't know exactly what.

Here you go...

 

[brokedownwallet]

Only one of the switches governs the front diff. The other sends a signal to Engine Control Module to do something but I don't know exactly what.

Here you go...

Thanks! Really appreciate it, about to hit the road and going all over the west coast so this will be nice to have wired in before then.

 

[brokedownwallet]

Only one of the switches governs the front diff. The other sends a signal to Engine Control Module to do something but I don't know exactly what.

Here you go...

Welp turns out I'm terrible at reading wiring diagrams, and getting to projects on time like repairing actual switches haha. What are the odds you could snap a photo of your bypass/tell me which wires to short on this photo? I know the goal is simply to close the circuit that swaps the VSV but finding it is more of the issue for me hehe.

[IMG]http://imgur.com/a/dGQ2huE[/IMG]