What switch does what when

[Clod_King]

Hey, so I got my hands on a relatively clean 1975 (or 76) TR7 a few months back. I'm doing things in a not so orderly fashion because money is a factor and when I run out I do the little things.

Well today I went out to investigate the headlights. They don't work. But that's not my immediate problem. The real problem is that some things work but mostly everything else does not work.

The marker lights work very well. In fact they work so well that they don't turn off. They come on as soon as I attach the battery leads. The passenger headlamp comes on when I push the switch on the dashboard down (I assume the drivers side lamp is just burnt out) but the brake lights and the blinkers do not work. The windshield wipers move as much as the pop up headlights do (well that's a lie because I can move the headlights manually).

But here is my main question. What do the switches do in this car? The switch in the dashboard I can safely assume should turn the head lights on (and pop them up if that function is still available) when pushed down, but is there an up? It looks strange sitting in that "mid" position and I am constantly wondering if it should go up as well as down... or push in or pull out, something else. And pulling back on the "stick" on the steering column should activate the high beams correct? And I guess pushing the same stick should perform the same function. Push up for right and down for left correct?

So what on God's green earth controls the marker lights? And why is the dimmer switch next to the cigarette lighter? And how did they bottle the dying screams of a banshee for the "door-a-jar" buzzer?


But really, just the first question needs to be answered. And this one: does the dimmer switch control anything else besides light in the cigarette lighter?

[XSeries]

The first position of the headlight switch turns on the side lights and marker lights. The second will then turn on the headlights. Taking it back to the middle position will lower the headlights again.

The rheostat dims all the dashboard lights the four that shine on the heater controls as well as the instrument panel.
The dip switch will flash the headlights, but only in the UK will they rise as there is additional circuitry (Pektron unit).

Interestingly it is also a Pektron unit that makes the seat belt warning sound (not really door ajar - there should be a switch to stop that from working unless the door is closed) - though a different unit which was also fitted to later TR6 models for North America as well as 7 & 8s.
Good luck
Brian

[Clod_King]

Thanks Brian. So what position will turn off the marker lights?

Also can I run the green wire from the turn indicator lights to the marker lights so that they make more sense to everyone else on the road? I wish I knew enough about electrical wizardry to have them stay on and then flash when I need them to...

[Hasbeen]

I am surprised, I thought as a king you would know all about the prince, prince of darkness that is, Lucas electricals.

I gather this Triumph has been sitting for a while. If so, don't try to get anything electrical to work until you have cleaned & coated with dielectric grease, every contact & connector in the electrical system.

For example, there are a bunch of connectors in the front of the engine compartment, some on each side. These drive various things in the headlight system, like the motors to raise them & the actual lights. Clean them & your other light will probably work.

I removed every globe holder from my tail light clusters, cleaned & greased them inside & out, & felt quite god like, when I had suddenly produced light where none had been before.

When I say everything, even clean looking fuses refused to pass power until removed, cleaned & sprayed with contact cleaner, & re fitted still wet with the stuff.

It includes removing every switch, disconnecting it from it's plug, & cleaning both. Inside the switches will need cleaning I expect, the gunk I have found in some of them was very surprising in our dry climate.

Don't forget all the earths, they are critical. One of my tail lights only produced any light from any globe after removing the casting, cleaning it ,the bolts, & where they attached to the body.

This should give you lots of critically important, but very inexpensive jobs to do each time the money runs out.

Oh, & welcome to the fold, & good luck.

Hasbeen

[Clod_King]

Yeah I cleaned the two major ground points in the light buckets and the one near the battery tray. That's when the buzzer started working again. It surprised the hell out of me to tell you the truth.

The car has been sitting for the last 20 something years in a garage and two years outside.

Yeah the Clod_King name kinda started on an RC forum back when I was 16 or 17.... it's been my consistent forum handle ever since.

That being said this isn't my first build, but it is my first British car. I haven't even heard it run yet, hahaha. My boss was moving and getting rid of it so I scooped it and he put it up in a shop across the street for me to work on it. It's got no power but it's still the best setup I've had to date.

I'm much better mechanically than I am electrically.

I'll get my hands on some dielectric grease and contact cleaner and start poking around tomorrow.

[prackers]

Mine had been sat 8+ years that I know of, probably considerably longer. Since it was a complete strip-down and rebuild a friend took my loom and replaced any dodgy looking connectors with new waterproof ones. However we didn't replace the numerous connectors that sit behind the dash since they "looked" to be in good condition. However on re-commissioning just about everything worked except the various headlight functions. After changing various solenoids/switches/headlight mechanisms and motors, all to no avail. The problem turned out to be the behind the dash connectors, pulling them apart they looked fine I used contact cleaner on them which helped but not 100%, the final fix was to expand the male connectors in the multi-plugs slightly.

[FI Spyder]

What Hasbeen said. Also disassemble switches by warming the old (and now somewhat brittle) plastic with a hair dryer. Take pictures particularly the headlight switch as it can go back together several ways, only one that is right and saves painstakingly figuring out N/O and N/C positions. You likely will find green goop in there like this hazard switch.

[Clod_King]

Well I went ahead today and recleaned the grounds I did earlier with contact cleaner and did a bunch of other connections with said contact cleaner and dielectric grease. Then I moved onto the headlight switch. It seemed okay to tell you the truth. Very very little green oxidization and even then it was at the base of only one contact in the switch. The actually spots where the electrical connections are made were clean and copper coloured. I sprayed them anyways and applied some grease.

Is it normal for the switch to be so difficult to return to the upper position? Mine seems to not want to go there. I can force it there, and there wasn't anything stopping it from going to that upper position but it really doesn't want to do it. I greased the tracks where the little white pegs ride and that did something, not much but something. It just feels like I'm gonna break the thing.

I didn't check to see if any of my cleaning made any difference but now I remember that I left the battery hooked up and I don't trust the car to remain powered and not light up like a gas soaked bon fire....

Oh, I also found a bunch of wires connected to that switch that were mangled with copper showing. I guess the last guy that was in there pinched them all and didn't resolve that little issue. No wonder I smelled impending electrical fire whenever I attached the battery terminals. (Hence my reasoning to go for another half hour drive to the car to unplug the battery....)

[Hasbeen]

You will probably find some connectors have been resoldered using acid flux. This causes the wire to corrode inside the insulation. The thing looks OK, but few if any wires remain to give power transmission.

Always suspect this if a circuit otherwise looks sound, but refuses to pass power. I have found a few where the connector falls off when the insulation is cut back.

Hasbeen

[FI Spyder]

My switch is harder to switch to the upper position, something that developed during the last 9 years. I attribute it to the white pin area, not enough lubrication, grease or wear. I seldom use it as I usually drive it during the day so haven't gotten around to pulling it to regrease.

[Clod_King]

So here is what the switch looked like before cleaning. Not too shabby eh?

I'll check out the other switches and wires because there seems to be something screwy going on back there. Looks to me like a quick fix gone wrong (for me). I am guessing that there weren't two sets of (distribution?) blocks wired in directly behind the hazard and fog light switches by the factory. You know those blocks with little bars with flat head screws on either end? I wish I took a picture of it, but my phone died. Either way its a joke question anyway because every wire coming off of that block to the switches are done in black. That's not factory for sure. Also they were soldered and I bet ya Hasbeen is right and even if they were initially hooked up correctly the wires are probably corroded to hell.

[FI Spyder]

Mine were much worse. I took mine apart and cleaned them with Brasso. They became a bright copper colour like the day they were punched out of the copper plate. Dielectric grease will help them stay that way. Repeat with every connection. 9 years of trouble free electrics. Well almost. I replaced a dodgy Delco brake light switch (at brake pedal) for a trouble free Lucas one out of my (other) older TR7. Oh, and a starter issue that ultimately boiled down to the positive battery cable clamp to battery wire connection were the lead in the clamp was deformed enough so it couldn't grab the cable tight enough. Discovered that one by accident. Wish my Acura was as reliable electrically (they have weak capacitors in the ICU that burn out and cause a myriad of glitches in the accessories).