Rewiring a 1970 FJ40 from scratch (1 Viewer)

[cuencanolenny]

I am installing a new American AutoWire (AAW) Hwy 15 harness in my 1970 FJ40. My wiring harness was a mess and consisted of color code red and black, black and black, and an occasional blue wire. I am using AutoMeter gauges and sending units. I built a new rear bumper as my rear frame channel had been butchered and later model turn signals had been installed, poorly, and they were slightly above dangling. The bumper wiring is similar to the gauges in that to remove the bumper requires unplugging forward of the rear channel and disconnecting a bullet for the license plate light.

At this point the starter/ignition bag has been installed, the alternator/charging is installed and I am now routing wires through the firewall to the front. I noted today that the sole power to the headlights is via the yellow wire to the dimmer switch. I will be installing relays for the headlights and there is plenty of wire to route to the left side and use the alternator and to the right side using the battery for power to the relays/headlights.

I popped the $100 for a new turn signal switch. The AAW instructions are based on a person using a GM or similar steering column. Consequently when I get to the loose ends of the wires it is up to me to figure out what to do. The FSM diagram (I bought the laminated, color, version on the net) looks pretty busy. I suspect part of that is the limitation on the size of the fuse panel vs the 15 circuit unit I now have installed. So here goes;

On the FSM diagram, power to the turn signal switch (TSW) is G via the Turn Signal Flasher which is fed from the fuse panel. There is a junction to the VR shown. The power to the Stop Light Switch (SLS) is a junction off the headlight switch to fuse panel. Power to the Hazard Switch is via an inline fuse off a junction to the alternator/ammeter wire.

I can take power to the TSW from the Purple Turn Switch at the Hwy 15 Fuse Panel (#7). I can take power to the SLS from the Orange wire at #9 on the Fuse Panel. It is easy enough to "Y" off of the GO & GY wires to go to the turn signals and stop lights, however, I'm confused regarding the Hazard Switch. The FSM shows a second flasher, my fuse panel defines the flasher as being for turn signal and flasher. Also there is a turn relay on the fuse panel. Operating from the water hose philosophy, if the hazard switch is "Off" there is no water passing through to it. So I should have turn signals and brake lights. But the FSM diagram looks very busy at the Hazard Switch with GY & GO (2 ea) feeding into the switch which shows seven connections. That looks very busy for what should be a DTSP switch. I am thinking that I can combine the GY wires and the GO wires at the hazard and then continue to the front and rear harnesses for turn at the front and turn stop at the back.

Does anyone see an issue with what I am proposing? Do I need to add a flasher for the Hazard Switch? Do I need to find a Hazard Switch with 7 connections? Thanks.

 

[cuencanolenny]

Rewiring 1970 FJ40

This is the rear bumper using Optronics rubber mounted trailer lights. I'm also not sure if I need a converter to use hazard lights with these units. With regards to the hazard switch wiring, I have attached what I found for wiring a hot rod and this is why the Toyota diagram seems a little busy. Your advice is welcome, thank you.

 

[Pin_Head]

It is a lot of work, but it is fairly straight forward. Remove the existing harness and label all the plugs. Then run new wires one at a time between the plug positions. Refer to the wiring diagram and try to use the same color wire for the same type of circuit like Toyota did. This will help others later on. You could also get one of the harness kits that has the labels printed on the wires.

Whether you need a trailer converter depends on the lights. If you have a separate bulb filament and wire for the brake lights and rear turns, then you need a converted. It would be cheaper and easier to just get new lights.

 

[cuencanolenny]

The new harness is labeled every few inches or so, they didn't offer it in Spanish though so the next guy may have a learning curve. The trailer lights are stop, turn, tail. Three wire connection but one is ground. I will probably need the converter to operate hazard lights.

 

[Pin_Head]

Solo en Ingles es mejor que nada.

 

[cuencanolenny]

Si. My wife is a native and now bilingual, however, when it comes to technical information her assistance sometimes complicates the translation. But I'm getting better at it as well as identifying which "tiendas" handle which kinds of parts. Very different from what I'm used to in the USA.

 

[bj40green]

Very different from what I'm used to in the USA.

Same in Costa Rica from what I'm used to in the Netherlands.

Rudi

 

[Pin_Head]

Very different from what I'm used to in the USA.

Pero tu tienes la dulce vida de los Ricos.

 

[DSRTRDR]

I posted a comment in the other thread (started by subzali) on how to rebuild the turn signal lever assembly and adjust it and the rod

 

[cuencanolenny]

I saw your message, thanks. I did clean the steering wheel end thoroughly in hopes of making it work. I also took apart the switch end to clean it up as well. However, once back together there was no change. It could also have been looseness in the driveshaft connections, they aren't nearly as tight as this new one is. Since I'm after some trouble free, reliable, electrical I decided to bite the bullet and go with all new stuff. I really hadn't planned on spending over a year to get this rig running, registered, etc. I bought it so I could go riding around in the mountains down here. I'll get there one of these days. Thanks so much for your input because sometimes folks observe something I've written, experienced, etc. and have valuable observations, such as yours, that a person may have not have thought of or overlooked.

 

[cuencanolenny]

Rewiring 1970 FJ40

Pin Head, instead of a fusible link this harness comes with a 175 amp "Mega Fuse" which I have mounted to the firewall on the right hand side. There are two oval cutouts in the firewall stiffeners and I fabricated a grommet for each of them for routing wires. Of course everything routes through a grommet when passing through sheet metal. I picked up more split loom today along with a few other items on the shopping list and can continue tomorrow with running my wires and cleaning things up like the alternator/regulator side.

 

[Pin_Head]

It looks like you have a good start on it. I think it goes faster if you have the whole thing out, but either way works. It will look much better when you get it bundled in looms.

 

[cuencanolenny]

It is probably my motorcycle history. This is actually the first car I have completely rewired but I didn't find it intimidating since there are so few circuits and they are quite similar to a motorcycle. Stuff may come back out to effect the final result I want which is clean and accessible. I would also want it to be easily removable should the vehicle come apart for painting.

 

[cuencanolenny]

Today was test day. It went pretty well. I turned the key to start and the motor was spinning. I don't have a gas tank so I will presume the rest of that circuit is operational. Next up was lights and I had tail lights and turn signals, but no headlights. I was going crazy checking circuits and then realized that with my new headlight relays I have an inline fuse installed. Oops, put a fuse in it. Of course the fuses I had don't fit! Jump on the bus to get close to Radio Shack, still a pretty good hike, and got some fuses and headed for home. Installed the fuses and voila, headlights hi and lo. The indicator on the new dash panel works as well as the blinkers for turn signals. But no side marker lights in front on parking light setting. Check it out and they needed to have a ground wire added. That done, they work fine. So everything is good, yes? No. I do not have brake lights. I used a jumper wire with a test lamp in the circuit and apply the brakes and the light comes on, let off and it goes out. Since that is the same filament as the turn signal I am perplexed. But it was getting late, around 6:00 or so and I needed to button up for the day. In the dimmer light I could also see that my dash lights work and dim as planned. My new dash gauge does not fit the hole in the car. The mounts for the instruments are rubbing in a couple of places and so I will have to file the sheet metal a little to get it to fit, no big deal. Pretty happy all in all considering how much wiring I did, the whole vehicle.

So Rudi, I need help. I did not wire in the hazard warning switch. It is shown as optional on the FSM wiring diagram and since I have questions on it I decided to skip it for the moment. On my AAW instructions there is a brown wire in the fuse panel that goes to the steering column disconnect. I have not run a wire out of that connection. That is page "D" in item #1. Since the turn signals and brake lights share the same filament I am perplexed.

 

[bj40green]

Good progress Lenny

Wise decision to save the hazard circuit for later.

Now for the brake/turn light.
You need this diagram to understand how it works:


The power for the brake lights goes through the turn switch.
When the turn switch is in the center position the power path is:
Stop Fuse, Stop Light Switch, in at Ss and out at RL and RR to light bulbs.

When the turn switch is in the left or right position the power for one brake light is uninterrupted but the power for the turn light comes now from B (from the flasher).

And here lies your problem. You have to figure this out with your AAW diagram.

On second thoughts...... if you don't have that "complicated" turn switch then my story doesn't fly.
Tell us which turn switch you have in your Cruiser. Top (6+2) or bottom (6+4)?


Rudi

 

[cuencanolenny]

Rewiring FJ40 From Scratch

http://www.cruisercorps.com/turn-signal-switch-1958-9-1971-oem.html

This is my switch, doesn't look like either of the ones you posted. Old and new are identical so this is not a non-USA issue in my opinion.

In the FSM diagram there is a red power wire that feeds the light switch. The brake switch GW receives power from this wire. In the AAW diagram that is the orange wire feeding directly to the brake switch. I have installed a 2 pin plug at the brake switch. In the FSM the GW then feeds the turn signal switch. In the AAW diagram the white wire is terminated in the steering column disconnect. I use the terminal "D" as I do not have a GM steering column. So on the white wire I attached a female bullet to match my brake light switch GW wire to complete the circuit. When I undo the 2 pin plug and run my test light in the circuit the light works with the brake pedal/switch.

In the FSM the turn signal flasher receives power from the fuse panel. On the AAW that is the purple wire and it feeds from the "D" connector to a female bullet at the turn signal switch which is the FSM G, center, wire. That leaves the four leads for the lights themselves, two each GY & GO. On the AAW that equates to the Y, Dk G, Lt Blue & Dk Blue wires leaving terminal "D" with female bullets to connect to the turn signal switch. On my FSM diagram the horn button does not appear to have any connection to the turn signal switch. Nor on the AAW diagram.

 

[bj40green]

Lenny, I'm going to send you a wiring diagram for a pre '72.
It uses the wire colors GW, GY, GY, GP, GO and GO which are the colors I think have seen on your Cruiser Corps switch.
The diagram is too big to post here but i'll try


I've tried. The forum shrinks the picture so you can't see the details.
The original is 4 times bigger.

Rudi

 

[cuencanolenny]

I got it all working. I feel so dumb. If you look at the Classic Car Wiring diagram above you will note a specific sequence to the six wires in the turn signal switch. Whether I "assumed" that GO & GY simply meant left side and right side or just can't see any twisting of the wires inside the Toyota sheath, there is a sequence. I disconnected the six wires and positioned the switch wires like the diagram and re-connected and everything worked. I wish I could say it is straight forward, and I guess it is, but what I really want to point out is that if someone else encounters this situation, switch the GO & GY connections before you spend a couple of days with jumper wires and trying every possible connection scenario you can dream of. I can now proceed with cleaning up the wires for length, installing split loom, finalizing some connections like the gas gauge, etc. When I'm done I will post some pictures of it all tidied up.
As an aside I would note that during my confusion I was doing a lot of research and some of that took me to the PDF's for Painless wiring harnesses. There is a lot of similarity to color coding with the American Autowire stuff, presumably buying wire from the same source with the labeling. But if the online Painless PDF is what comes with their kits then I would say that the American Autowire is far superior with regards to instructions. Not to mention quite a bit cheaper. I paid $319 for the Hwy 15 kit from Summit Racing. While I also ordered some additional connecting plugs, bullets and spades from Cycle Terminal, I haven't used nearly as many plugs as I bought but I did use quite a bit of the other stuff making good clean connections as well as re-doing a few as I proceeded through the installation. As noted, I will be shortening some wires and I will do that at the kit plugs rather than in the middle of the wire so I will use more of the spade connections. Thanks to Rudi and Pin Head for their help, great resource here on MUD.

 

[cuencanolenny]

FJ0 Wiring Harness From Scratch

Looking a little cleaner now. I have a couple of more circuits to run once I receive new switches but they will be very easy to install. All in all I give the American Autowire Hwy 15 wiring harness a 9. For a universal kit this went very smoothly. Excellent instructions and equipment included in the kit. I had already purchased a new Toyota ignition switch, door and lift gate locks that I had re-keyed to the ignition so I didn't use the supplied ignition switch, although it would have been easier using it. Of course I don't have the GM steering column but this did not present much of a problem once I figured out what to do. It takes me a lot longer to do things than most people, being clumsy adds a LOT of time.

Headlights have relays for hi and lo on both sides. I routed wires from the center of the firewall to the right and left so the right side relays power off the battery and the left side off the alternator. There are inline fuses on both sides and I used 12 gauge wire. On the left I see a zip tie tail that needs to be cut. Then we see the routing of the wires on the left side and then the right side. I had sized and ordered grommets for various holes, made grommets for the oval cutouts at the lower end of the firewall stiffeners.

 

[cuencanolenny]

1970 FJ40 Wiring Harness From Scratch

You folks in the cold climates will envy the convenient placement of the fuse panel. Heater not supplied with this rig here in Ecuador, pretty basic vehicle. I routed the chassis harness inside the right frame rail and pulled the fuel gauge wire out at the appropriate location. I drilled and tapped the frame rail on the outside for the fuel gauge ground wire. The rear bumper is fully wired and uses a plug for disconnect. Inside the rear frame rail I routed the license plate light wire and it connects via a bullet.