Hi, All, I've had to unexpectedly replace the wiring loom on my 1963 Golden Flash. I have no knowledge of how to go about this but thought I'd give it a try, I've hit a problem already, there are to brown wires to the stop light switch, I presumed one to be pos and the other neg but that doesn't seem to be the case as when I connect my circuit tester across the two wires nothing happens. One is def positive as I get a circuit from that and back to the neg battery pole.I haven't wired the rest of the loom yet so maybe the earth will become apparent then? Anyone know what these two identical colour wires are??
One wire feeds from battery the other goes to the stop light. It does not matter which way around. You will only get a complete circuit when the switch is "on"
Check the in line fuse if it came with one, had a horror story with a new Lucas loom from Ebay.
Quote from: JulianS on 01 Jun, 2020, 14:27
One wire feeds from battery the other goes to the stop light. It does not matter which way around. You will only get a complete circuit when the switch is "on"
ditto, the switch is in line. for confusion, light switches in houses used to be twin wire red and black, the black had a small sleeve of red on it.
Thank you for your comments, as I said in my original post my knowledge is limited. If I have the positive and negative wires connected to the battery and put a circuit tester between both wires shouldn't I have a complete circuit? because I don't.
No you won't have a circuit as the positive and negative terminals are on different plates in the battery. You will get a reading if you use a voltmeter. If your circuit tester is in fact ohmmeter then it will not show a resistance so no reading.
Hi,
Wiring diagram is the 1st attachment.
The brown wire from the battery (-ve) to the switch and onwards to the stop lamp is the power supply. The frame is the +ve, known as positive earth. The rear and stop light is earthed as shown on 2nd attachment to make a circuit, A TO A.
To test this supply, first put the circuit tester on the -ve on the battery and its +ve on an unpainted part of the frame, you should have a circuit.
Then put the circuit tester as shown on 3rd attachment, testing the connection from battery to stop switch, B to B.
Then as the 4th attachment, depressing the rear brake to operate the switch C to C.
Then depress the rear brake to operate the switch, this should light the stop lamp if the earth at the rear lamp is good.
Best wishes...
Thanks to all of you for your help. I will put that information to practice. I'm sure this won't be the last time I will require your help with this loom project. I know I am out of my depth.
It's worth adding that if your leaving the battery in circuit then you must select the multimeter to volts (DC if it's selectable) with a range no higher than 10 or 20.
If your wanting to check the resistance of the circuit and thus fault find for any problems then select ohms (Ω) . However it is crucial that you remove the battery from the circuit as the voltage may permanently damage the multi meter.
You'll not see a voltage reading at the wires feeding the switch because a positive and negative are not fed into a switch. Remember that a switch just needs to create a break in one wire feeding the brake light bulb to turn it off or on, therefore placing a multimeter on the 2 wires feeding a swich will show no voltage reading. I hope this makes sence and is not tooooo confusing. All the best, Glenn.
forget the meter if getting confused, put each end of the wires on a bulb, bulb should be on.
leave the bulb on one side and put the switch between bulb abd the other brown wire. bulb should be off, operate switch and bulb goes on and off
That's what I am doing, What I meant by a circuit tester is the testers you buy in Halfords that look like a screwdriver with a bulb in the handle.
If you connect a circuit tester to both sides of the switch it won't light. Both sides of that switch are feed until they reach the bulb. What you want to do if you haven't already is connected the crocodile clip at the positive on the battery. Then touch both sides of the switch in turn. One side will light up. The other won't until the switch is pressed.
If your using the 60 on type switch which bolts
To the back of the tool box, these only make a connection for the period of time when the lever is not at either end, ie works for the middle Portion of the switch movement.