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TR4/4A 4A Wiring loom quesstion
- Thread starter HarryL
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TR3driver
Great Pumpkin - R.I.P
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One trick is to power each circuit through an old headlight bulb first. If there is a short, the bulb just comes on brightly with no harm to anything.
But if you've checked each circuit as you went along, before connecting the load, then it should be reasonably safe to "just turn the key".
But if you've checked each circuit as you went along, before connecting the load, then it should be reasonably safe to "just turn the key".
So this says how far I have moved ahead. Placed the battery in and hooked up the battery posts.
On the solenoid should the small spade(r/w) be hot ? I would assume once the key is turned over for the starter
the other post would go hot ? This did not happen . Bad Solenoid ?
Harry
On the solenoid should the small spade(r/w) be hot ? I would assume once the key is turned over for the starter
the other post would go hot ? This did not happen . Bad Solenoid ?
Harry
Geo Hahn
Yoda
Offline
On the solenoid one of the BIG cables should be hot. The red/white wire is hot only when the key is turned to the 'start' position, not hot when the key is in the 'on' or 'run' position. In the start position that r/w wire causes the solenoid to operate (distinct click) and the second BIG cable (to the starter) should be hot.
trrdster2000
Luke Skywalker
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Harry, put a ground strip at the front, under the grill, run a large wire to the chassis and attach the ground wires from all of your lights to the strip. You will have brighter lights all around.
Wayne
Wayne
DNK
Great Pumpkin
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trrdster2000
Luke Skywalker
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Harry, most green wires or green white, green red and so on, go to the lights or some light switches, it should go to the same fuse as your coil wire, but not fused, weird!
Wayne
Wayne
martx-5
Yoda
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Major colour groups are as follows:
Here's a list from Moss that has some of the other major colours.
Brown Battery circuit. From battery or starter switch to ammeter or control box and (with compensated voltage control feeding lighting and ignition switches (and radio, when fitted) from control box terminal. Also, from starter switch to electric clock, inspection sockets and battery auxiliaries fuse (from which are fed electric horns, cigar lighter, interior lights, etc.).
Yellow Generator circuit. From generator terminal to corresponding control box terminal and to ignition warning light.
White Ignition circuit and all requirements essential when ignition is switched on but which do not require fusing, e.g., electric fuel pump, starter solenoid switch, ect.
Green Auxillary circuits fed through ignition switch and protected by the ignition auxiliaries fuse, e.g., stop lamp, fuel gauge, direction indicators, windscreen wipers, etc.
Blue Headlamp circuits. Fed through terminal on lighting switch.
Red Side and tail lamp circuits. Fed from terminal on lighting switch. Included in these circuits are fog lamps, panel lights and other lamps required only when the side lamps are in use.
Black Earth circuits. If a component is not intemally earthed, a cable must be taken to an earthing point on the chassis.
Edit: Here's a list of the colour codes with the tracers, but be careful, as cars up until 1983 might not apply.
https://www.bmcautos.com/projects-blogs/60
| Main Color | Purpose |
|---|---|
| Brown | Hot all the time, unfused |
| Purple | Hot all the time, fused |
| White | Hot with ignition on, unfused |
| Green | Hot with ignition on, fused |
Here's a list from Moss that has some of the other major colours.
Brown Battery circuit. From battery or starter switch to ammeter or control box and (with compensated voltage control feeding lighting and ignition switches (and radio, when fitted) from control box terminal. Also, from starter switch to electric clock, inspection sockets and battery auxiliaries fuse (from which are fed electric horns, cigar lighter, interior lights, etc.).
Yellow Generator circuit. From generator terminal to corresponding control box terminal and to ignition warning light.
White Ignition circuit and all requirements essential when ignition is switched on but which do not require fusing, e.g., electric fuel pump, starter solenoid switch, ect.
Green Auxillary circuits fed through ignition switch and protected by the ignition auxiliaries fuse, e.g., stop lamp, fuel gauge, direction indicators, windscreen wipers, etc.
Blue Headlamp circuits. Fed through terminal on lighting switch.
Red Side and tail lamp circuits. Fed from terminal on lighting switch. Included in these circuits are fog lamps, panel lights and other lamps required only when the side lamps are in use.
Black Earth circuits. If a component is not intemally earthed, a cable must be taken to an earthing point on the chassis.
Edit: Here's a list of the colour codes with the tracers, but be careful, as cars up until 1983 might not apply.
https://www.bmcautos.com/projects-blogs/60
Last edited:
Geo Hahn
Yoda
Offline
Usually green wires are fused power circuits (e.g instruments).
Nice diagrams here: https://www.advanceautowire.com/tr24a.pdf
I see no green wire to the ignition switch -- is this a new harness you are installing?
Nice diagrams here: https://www.advanceautowire.com/tr24a.pdf
I see no green wire to the ignition switch -- is this a new harness you are installing?