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- #301
A bit of strategizing, before I start hacking, soldering, crimping, connecting, switching, and hopefully not smoking.
Builds Project "Devil Frog" - Isaac's '69 FJ40 (2 Viewers)
- Thread starter Devil Frog
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alia176
SILVER Star
Show us your connectors!
- Thread starter
- #303
I’m debating on going weatherpack or Deutsch
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- #304
I found weather packs locally so that’s the way I went.
Look at you being all nerdy and drawing wiring diagrams on engineering paper.
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- #306
I had a pad that was over 10 years old and don’t have Visio, so yep best tool I had for the job.
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- #307
So the stock airflow meter is going in the trash and has been replaced by (to run a speed/density fueling algorithm):
- MAP (manifold air pressure) sensor and
- IAT (intake air temperature) sensor
The dilemma is that the stock airflow sensor also had a safety function. When air is isn't flowing it doesn't allow current to a relay that controls the fuel pump. I can just short these wires to get the fuel pump to work, but then the safety function is gone, so if I wrecked the vehicle and a fuel line got ripped out, fuel would spray even if the throttle blocked the air from the intake. Alternatively I could wire in a fuel pressure sensor, that would open the relay if fuel pressure is lost.
Also, I am running the fuel pump control through my programable ECU, so I can set conditions where the ECU kills the fuel pump for a variety of conditions:
Thoughts?
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Seems like the programmable ECU will take care of the safety concerns. Do you trust it? Do you want to have a mechanical hardware backup to black magic software?
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- #309
I don't have distrust of software relative to electromechanical HW, when neither are designed or certified to be safe in an uncertain and hypothetical accident scenario. I think it is prudent to have at least one positive measure so it lessens the risk fuel doesn't get sprayed everywhere. I am leaning toward just the ECU as the safety device.
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Programming seems less involved than extra hardware.
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- #311
Had to splice in an aftermarket EFI relay because the OEM one is discontinued. I got my ECU talking to the laptop. Also pliced in the GM intake air temperature sensor and verified that’s working, I think I have a bad throttle position sensor, so that’s the next thing to troubleshoot.
- Thread starter
- #312
Does polarity matter? Well, it depends.
I got myself a pair of LED head lamps, they looked to be PNP, but the brights wouldn't light up. I could measure 12V across Fj62 donor harness terminals on dims and high beams, but nothing when the lights were plugged in. I almost sent the headlamps back, but then I made an important realization. LED = light emitting diode. I am by no means a gEEk or sparky, but a diode will only let current travel in one direction around a circuit, so polarity matters in this case.
Now take a look at the clever Fj62 circuit design:
Things to note upon instpection
I took me some thinking, but I cam up with a solution:
Headlamps work like a charm now, not bad for a knuckdragger ME. Also thanks again to Jon for his advice and pioneering work in retro-modding Fj62 electronics into an early Fj40
I got myself a pair of LED head lamps, they looked to be PNP, but the brights wouldn't light up. I could measure 12V across Fj62 donor harness terminals on dims and high beams, but nothing when the lights were plugged in. I almost sent the headlamps back, but then I made an important realization. LED = light emitting diode. I am by no means a gEEk or sparky, but a diode will only let current travel in one direction around a circuit, so polarity matters in this case.
Now take a look at the clever Fj62 circuit design:
Things to note upon instpection
- The low beams are +12V
- but the high beams are -12V
- and the returns are not grounded, they are floating and flip states with the dimmer switch
I took me some thinking, but I cam up with a solution:
- use a permanent ground to chassis
- use a DTDP relay to change the constant +12V (red/wht driver, red/bue passenger) between low and high beam
- low beam is NO
- high beam is NC
- I used the FJ62's secondary highbeam lamp to run through the relays solenoid to switch states since a FJ40 has a single headlamp per side
Headlamps work like a charm now, not bad for a knuckdragger ME. Also thanks again to Jon for his advice and pioneering work in retro-modding Fj62 electronics into an early Fj40
- Thread starter
- #313
Fixed the problem with the TPS. Found out there was a short somewhere between the TPS 5 V supply on the sensor end and the connector on the ECU end (the joys of retrofitting a used harness), luckily the 5 V supply is common with what was used on the OEM MAF, and that is not needed anymore so I was able to run a jumper from one to the other, which solved the problem. TPS works like a charm now. I need to spend some time cleaning up the wiring.
Nice progress! Looking forward to see it on the road.
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- #315
So I’m getting back at it again, I got my vintage air unit, which was holding me up in completing the wiring and plumbing. I also got a much better welder, and decided to go back and re-fabricate some brackets, like the one for the York compressor. I love this Millermatic 220 AC/DC. It’s night and day next to that 110 V flux core unit. I can actually use decent thickness material and have clean welds without all the grinding.
alia176
SILVER Star
Dude - Isabelle is gonna graduate from high school in two years so get a move on already. I think she was in elementary school when you started this project 
Don't listen to him. I took all kinds of abuse when I did my project.Dude - Isabelle is gonna graduate from high school in two years so get a move on already. I think she was in elementary school when you started this project
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- #318
He’s right, it’s always been my third or fourth priority. I’m finally at a point where I have all the major parts I need, and I have a dedicated place to work on it so. I welcome to smack talking now, I need some fuel to just get it done
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- #319
One step forward two steps back. I had my wiring about 70% done, but could not physically tuck the FJ62 cowl harness neatly under the dash with the vintage air unit there. It was too long and bulky from all the "fancy" circuits the Fj62 has that I don't need, plus there was a fuze box and relay. I made the strategic decision to ditch the FJ62 wiring harness and go with a custom hot rod harness. This will be much cleaner, though in the short term I need to redo much of the work. I will still use the pigtails for many of the components I cut off the FJ62 cowl harness, in particular the engine electronics, some of the relays, and column, so procuring the FJ62 harness was still worthwhile.
An issue I am running into now is that the Toyota alternator has a 3 pin connector and this harness only has provisions for a 2 pin.
From the FJ62 WD Looks like one of the pins was for a charging light circuit controlled by a relay. I am thinking about either eliminating or inserting an ammeter there. Any complications with doing so?
An issue I am running into now is that the Toyota alternator has a 3 pin connector and this harness only has provisions for a 2 pin.
From the FJ62 WD Looks like one of the pins was for a charging light circuit controlled by a relay. I am thinking about either eliminating or inserting an ammeter there. Any complications with doing so?
All I will say is I have the charge light relay on mine. It's wired per the wiring diagram ... and the light is on all the time. I have no idea why.