From this thread one issue is the back up lights. Going from park to drive may be the short.
10 amp gauge fuse keeps blowing
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From this thread one issue is the back up lights. Going from park to drive may be the short.
I have the
Was it in the factory wiring or in the trailer wiring? Did yours cut out when the truck was idling or only when it is moving?
This does seem possible. I thought I had made a break through the other day when I had left the truck running with a new fuse while in Park, but then as soon as I shifted into reverse it killed the fuse. However, yesterday I was back in there and I got the fuse to stay alive while shifting from P to R and then to D. I only made it about 20 feet on level, dry alley pavement and it blew again. I had the center console out and all of the wires in there look fine, but I kinda stink at testing things and don't trust what I am getting for results. I did disconnect the speed sensor to see if that might be causing it and it didn't help keep the fuse viable.
I am wondering about this diode(for neutral indicator) or the Electronic Controlled Transmission Pattern Select SW unit. Is the latter a wire or some sort of junction box? I am not sure if I am going to solve this by myself, but I would like to give the shop as much info as possible.
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Is the engine harness touching the EGR pipe?
No. I recently replaced the head gasket and when I did that I checked the wires in that area and wrapped both that section of the wiring harness and the EGR pipe with fiberglass tape. This problem existed before I did any of that work and it continues.
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My next step would be to start unplugging main harness connections, until you find the one that causes the problem. Once it's narrowed down, becomes easier to find. I would start with the tail light harness in the driver kick panel, confirming/eliminating the stuff in the rear.
Find this, along with a box of fuses, helpful, can see exactly when the load happens. The only issue I have with it is; the auto off is too quick, have to keep turning it back on.
30 Amp Automotive Fuse Circuit Tester
Find this, along with a box of fuses, helpful, can see exactly when the load happens. The only issue I have with it is; the auto off is too quick, have to keep turning it back on.
30 Amp Automotive Fuse Circuit Tester
Do you mean the taillight relay in the kick panel? So I should take that out and see if it trips the fuse when I drive it?
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The Toyota harness is modular, made in sections, so sections can be unplugged. The tail light harness is pretty easy to unplug in the driver kick panel.
I see. I just got back from a little drive. I had pulled the taillight relay and the truck went as far without blowing that it has for several months. I am not sure if the two are related though since it blew when I was pulling out of Napa(buying more fuses, lol). I did kinda jump the curb on the way out and that's when it blew. My relay does have a little rust spot on it though so I may buy a new one anyway.
I will try to monkey around with the wiring harness for the taillight. Do you know what the section is called in the Factory Wiring Diagram? On page 32 there is a wire called the No. 1 Floor Wire that looks like the one that goes to the rear lights. Is this it?
Also, the junction connector J4 which seems to be what you are talking about says it is orange, but I don't see any orange connectors under there. Is the color referring to something else?
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I think I've narrowed mine down to not be something from the rear of the vehicle. I unplugged the main harness that goes rearward by the driver footwell and still have the same issue.
Based on how it appears (missing areas of loom, wet with oil from leaks) I think its somewhere on the transmission/tcase harness. When I'm back in town I'll pick up where I left off in that area.
Thanks for the tip Tools R Us.
Based on how it appears (missing areas of loom, wet with oil from leaks) I think its somewhere on the transmission/tcase harness. When I'm back in town I'll pick up where I left off in that area.
Thanks for the tip Tools R Us.
I am confused. Did the harness you disconnected look orange? The one in the wiring diagram on page 70 shows J4 as the connector to the back up light. The taillights are on another circuit I think. It seems like I need to take the dash apart again to see this J4 connector and see if any of those wires seem to be shorted. It's not near the kick panel by the door in the wiring diagram book.
The rear harness I disconnected had a white large plug. Along with the harness is the rear windshield washer fluid line.
Chris FJ80
SILVER Star
I had the exact same issue and same cause: A/C clutchA lttle background on the problem I had: I was driving down the road here in Tucson with the A/C on. It was about 100 degrees outside and all of a sudden the A/C shut off and the gauges in the dash stopped working. After replacing the fuse, everthing was fine until i turned the A/C compressor back on, the fuse blew again. It only happend when I turned the A/C comprssor on, not the blower fan, heater, rear heat, or anything else on the heat/A/C control panel. So, I took a Toyota wiring schematic for the gauge circut and began testing things on the circut. At first, all indications pointed to the A/C cut relay behind the main engine computer. After I replaced that, the problem continued. So, I took the test further and now determined that the clutch on the compressor is the culprit. It was pulling about 20 amps and i THINK it is supposed to pull about 5 or 6. But, while i was there i found that the compressor is aftermarket anyway and Toyota sells the clutch and the compressor as one piece for the 1FZ.
I hope my living without A/C in Tucson for the past 2 weeks without A/C could maybe help you identify a problem quicker.
Cheers
Narrowed it down to somewhere on the transmission/transfer case wiring harness via the large grey square plugs near the starter (once disconnected the short was gone and the gauges worked). I'm in the midst of pulling the transmission/transfer case wiring harness to fully diagnose.
Thanks for the update. I called my mechanic last week to let him know that I wanted him to check these areas as i had read several threads where people reported shorts or other issues with these wires. It does make sense, especially since those wires are exposed to the elements and at least my truck has plenty of rust underneath.
Let us know what you find and I will do the same.
Mine did the same when I bought it. I found the trailer lights connector wiring had rubbed through causing a short in reverse. I repaired the trailer wiring and haven't had the issue since.
Well, the guy I had looking at mine gave up. I am back to the drawing board. I am going to check some of the spots that others have mentioned when I get back from holiday travel. I have another person that is willing to take a look at it but I am starting to get concerned that this might be the end of this truck. It's a shame that I did all of the work I have already done to the truck like rebuilding the top end of the motor, rebuilding the front axle, all new brakes and a bunch of other smaller projects, but I can't really drive it without heat and all of the other things that this stupid fuse operates. I have been a Toyota fan for as long as I can remember and have had more than 10 of them but I have to say that this circuit was a mistake in my opinion. Why would they have SO MANY things running off of just this one 10 amp fuse? It's ridiculous.
At this point dumping more money into it really isn't the end of the world as I have more into the truck now than it is likely worth and nobody is going to buy it anyway unless I get this fixed. At this point, parting it out would probably be my best bet if I can't get this figured out.
The guy I had looking at it mentioned something about there being a new infrared device that the tool companies are selling that can be used to pin point shorts. Does anyone know anything about that and if so, what it is called? He said they were crazy expensive, but maybe I could find someone that bought one if I knew what I was asking for.
At this point dumping more money into it really isn't the end of the world as I have more into the truck now than it is likely worth and nobody is going to buy it anyway unless I get this fixed. At this point, parting it out would probably be my best bet if I can't get this figured out.
The guy I had looking at it mentioned something about there being a new infrared device that the tool companies are selling that can be used to pin point shorts. Does anyone know anything about that and if so, what it is called? He said they were crazy expensive, but maybe I could find someone that bought one if I knew what I was asking for.
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I rebuilt the transmission/transfer case wiring harness yesterday (not really necessary it turns out, but at least all of the wires have been inspected 100% - with all new loom and tape). While reinstalling the wiring harness I installed a new fuse and checked if the gauges worked after each wire was connected and have traced it down to the vehicle speed sensor (the large connection at the rear). Next step is to test the VSS and wiring leading directly to the VSS with the multimeter.
Red Merle - don't give up just yet. When this short occurred I was in the same boat at first just really guessing where it might be since so many things are connected to this circuit. The best advice I've received thus far is to disconnect the sub harnesses at major points to isolate the problem. For example when disconnecting the harness that covers much of the rear wiring I still had the issue, taking all of the taillight circuits and such off the list. The next move was to disconnect the trans/t-case wiring harness and the fuse no longer blew, isolating it to somewhere on that harness.
Red Merle - don't give up just yet. When this short occurred I was in the same boat at first just really guessing where it might be since so many things are connected to this circuit. The best advice I've received thus far is to disconnect the sub harnesses at major points to isolate the problem. For example when disconnecting the harness that covers much of the rear wiring I still had the issue, taking all of the taillight circuits and such off the list. The next move was to disconnect the trans/t-case wiring harness and the fuse no longer blew, isolating it to somewhere on that harness.
I think you are right about disconnecting sections. I just spent a couple of hours digging around with no luck yet, but I did disconnect the junction that runs through the storage port in the back on the side with the jack and the other panel on the passenger side. A couple things looked a little suspicious so I pulled some tape back and inspected, cleaned one of the ground points by the trailer hitch and inspected those as much as I could. I re-wrapped everything and tried disconnecting that junction block and I still have the short when I slam a door.
I also looked at some of the clips that tie into the trans and the transfer case, but I am not really sure if those were on the same circuit. There is one big one on the driver's side of the trans that is covered by a metal plate and looks like it means business, but I am not sure if that one is on the circuit. It does look rusty, but getting the plate off might be a challenge since there also appears to be some sort of cotter pin on one of the nuts(all rusty as heck, of course).
Where is V1 located on your truck? Could you snap a pic of that area? Part of my problem is still that I suck at knowing which wires are part of the circuit and which ones aren't. As you know, there are a lot of wires under there. Did you start from the fuse and go back or did you have another way of knowing you were messing with stuff on the circuit?
Do you have the EWD book for a 1994?
