TR2/3/3A Pictures Under TR3A Dash

[Tugboat]

Hello All,

Due to my recent electrical investigations recounted in another post I am going to revisit my dash panel wiring tomorrow. As part of that process I intend to impose order upon the spaghetti mess of wiring from the overdrive, heater, and dash panel currently hanging down. Does anyone have a good picture looking up from the floor at the area behind the dash so I can see how it ought to be done?

Thanks Much

 

[JFeher]

Here'a picture of mine when I took it apart.

 

[Tugboat]

Thank you John.

 

[ekamm]

That looks pretty stock here are a few of mine. I used some wiring numbers and short pieces of wire to mark where I removed a wire and then marked the corresponding wire on the harness. If you search the archives you can see where some guys have cleaned up the mess quite a bit.

 

[martx-5]

Looking at those pics, spaghetti seems to be the norm...

 

[mrv8q]

If your temperature gauge is working, you'll want to be careful w/ the sender tube behind it. It's filled w/ ether, and a good kink in the tube might crack it enough to release the ether... Be gentle there.

 

[Geo Hahn]

Here's a pic I swiped off of eBay once upon a time.

Not exactly stock (e.g. connectors) but does demonstrate that is does not have to be pasta.

Of course as you look at examples bear in mind that the rear view changed when the panel lights got a rheostat (at TS60000?).

 

[Tugboat]

Thanks Fellows,
I have some stuff working but am working my way through the stuff that does not - wipers and dashlights - and find these pictures invaluable.
Mike

 

[mrv8q]

Does your car have the inline fuse directly under the 4 gauge panel? Later TR3s had an in-line fuse there.....

 

[Tugboat]

Kevin,
Yes, I have the in-line fuse. I am finding that there are subtle variations in the various wiring diagrams. It is foggy up here today so I hope to work it all out over the course of the day.
Mike

 

[TR3driver]

I am finding that there are subtle variations in the various wiring diagrams.

If your car has the rheostat for the dash lights, this diagram should be close (except for LHD vs RHD).

Otherwise this one should be right.

 

[Tugboat]

Thanks Everybody,
After burning though a weekend, 6 fuses and many brain cells I think I am almost there. The breakthrough was a post by Randall on another site in 2007 about connecting the panel switch to the headlight switch. Once I did that everything seemed to work so I reinstalled the dash panel and reattached the oil line to the oil pressure gauge and then started it up. Everything worked, even the temperature gauge, and the new voltage stabilizer which got me started on this wild goose chase in the first place. The only hiccup is that when I went to turn the key to kill the engine, it did not work, i.e the engine continued to run. Which is odd because I don't recall doing anything with that particular switch while I had the panel out. Fortunately, that is the one switch I can most easily access, hopefully without having to pull the panel again. Appreciate all of the help.
Mike

 

[TR3driver]

Which is odd because I don't recall doing anything with that particular switch while I had the panel out.

At the risk of stating the obvious, the problem isn't necessarily with the switch, or even near the switch. For example, a mixup at the fuse block could cause the same problem. Basically anything that feeds power into the white or green circuits.

BTW, that inline fuse is supposed to be between the panel switch and the headlight switch.

 

[Tugboat]

Randall,
Yeah, I now know about the in-line fuse thing. Must have seen it on all of the potentially applicable wiring diagrams, including the ones you sent me, but it did not click until I saw your 2007 post. In response to your subsequent post, I agree with you about the green circuit. I am thinking the problem has to do with the wiring coming off of the fuel gauge and/or the wiper switch. The various diagrams show one green wire going from the fuel gauge to the wiper switch but when I do that I can never get the switch to work (the other two wires go to the sender and the fuse box). The wiper switch will work when I do not run a green wire from the fuel gauge but instead run a wire from the switch to the nearby ground post. Running both the wire from the switch along with the green wire from the fuel gauge to the ground post blows a fuse (number 7!). Sooo, I am in a bit of a quandary. On the positive side (sorry) I can now pop that panel out in less than a minute, including the oil pressure line. Any (further) wisdom is greatly appreciated.
Mike

 

[TR3driver]

The various diagrams show one green wire going from the fuel gauge to the wiper switch

Only ones that are for cars much earlier than yours! Some of those differences aren't all that subtle :laugh:

<div class="ubbcode-block"><div class="ubbcode-header">Quote:] The wiper switch will work when I do not run a green wire from the fuel gauge but instead run a wire from the switch to the nearby ground post.[/QUOTE]Which is the way it should be.
<div class="ubbcode-block"><div class="ubbcode-header">Quote:] Running both the wire from the switch along with the green wire from the fuel gauge to the ground post blows a fuse (number 7!).[/QUOTE]Hopefully, that one is obvious? A direct short from the green circuit to ground ...

 

[Tugboat]

Randall,
None of this is obvious to me. I only dimly understand electronics so I try to follow the instructions (and occasionally freelance and blow fuses). The later wiring diagrams show two green wires attaching to the fuel gauge. I have three. One goes (I assume) to the sending unit. As to the paired two on the other post, one goes to the fuse box but where does the other one go? Sorry to be obtuse about all this but you're not dealing with a rocket scientist.
Thanks
Mike

 

[TR3driver]

Most likely, the mystery green wire goes to the heater (which not shown on the factory diagrams). Of course it's possible that some previous owner has tried to follow the early wiring diagram and mistakenly ran a green wire to the wiper switch, but the heater would be my guess. One way to find out would be to disconnect it, and see what stops working.

BTW, the wire to the sender should be green with a black tracer. It's important which is which, as the gauge won't work right if it is hooked up backwards.

Also BTW, one way to avoid using up fuses is to use a headlight bulb as a temporary fuse. If nothing is shorted, the bulb will only glow dimly or not at all. If you have a short, the bulb will light brightly. You can use a couple of test leads

to hook it up. I keep a selection of "burned out" headlight bulbs for just that purpose; almost always only one filament is bad so you can use the other one for testing.

 

[BRSLimited]

I have a self resetting circuit breaker I jumper in for the fuse for testing. No more blowing expensive fuses.

 

[Tugboat]

Thanks Again Everybody,
Mission accomplished. Randall, you were correct, the mystery green wire coming off the fuel gauge connects to the heater. It still took me a couple of days to run off various gremlins - but for now, everything works.
Mike

 

[af3683]

Can anyone please verify the size of the 6 dash bulbs and whether they can be purchased at your local auto parts store. Thank you.

Art