15-07-2021, 03:18 PM
This might be useful, but what year is your car?
This car is wired NEGATIVE earth.
It always has been negative earth,
positive earth was not introduced until 1936.
item Colour of wire Position of wires
Negative battery lead to the starter motor casing, and to the body, bolted to the battery box.
Black
The positive battery lead is connected to the starter motor terminal. Black
Everything else is earthed to a nearby body earth point. Black
Everything is powered by a thick wire from the starter motor which goes
to
the isolator switch behind the dashboard
Yellow/black
This thick wire continues from the isolator switch. to the ammeter Yellow/black
From the second terminal of the ammeter to electronic voltage regulator Brown
From the second terminal of the ammeter to Ignition switch , A. White/purple
From ignition switch , A. to Non-ignition fuse White/purple
Linked from non-ignition fuse to Lighting fuse White/purple
from Lighting fuse to Light switch White/purple
From Light switch to Dipswitch via fuse Blue
From dipswitch to Main beam headlight via junction box in car Blue/white
From dipswitch to Dipped headlight via junction box in car Blue/red
From light switch to Fuse, then Sidelights via junction box in car Red
All sidelight wiring from junction box to Front sidelights Red
All sidelight wiring from junction box Through o/s roof and across in boot Red
NOTE…
SIDELIGHTS AND
offside INDICATORS
ARE BOTH RED
RED
From ignition switch, IG to Ignition fuse White
From ignition switch, IG to coil White
coil to distributor White/black
Ignition fuse to Brake-light switch Green/
purple
Brake-light switch to Brake-lights Green/
purple
Junction
Front indicator offside Underbonnet
junction box Os wing red Os wing
Rear indicator offside Underbonnet
junction box Os rear red Os roof
Front indicator
nearside Underbonnet
junction box ns n/plate red Os wing
Rear indicator nearside Underbonnet
junction box ns rear red nearside roof
j/box f/box j/box red b/head
Brake lights brakelight switch Nearsides st lt Green/
purple Nearside roof
Offside Brake lights to nearside Brake lights Os st lt Gr/purp boot
Centre st lt ns st lt cent st lt Gr/purp boot
Centre tail Ns tail cent st lt red boot
h/light h/l sw f/box blue dash
h/light f/box Dip sw blue In car
h/light main Dip sw j/box Blu/wh In car
h/light dip Dip sw j/box Blu/red In car
h/light main j/box Os h/lt Blu/wh Os wing
h/light main j/box Ns h/lt Blu/wh Ns wing
h/light dip j/box Os h/lt Blu/red Os wing
h/light dip j/box Ns h/lt Blu/red Ns wing
coil Ign sw coil wh Os wing
coil coil dist Wh blk Os wing
Dynamo D dynamo f/box yellow Os wing
Dynamo D f/box reg yellow b/head
Dynamo F dynamo fuse green Os wing
Dynamo F fuse reg green In reg
Horn sw j/box horn yellow X BULK
Horn horn aux purple X BULK
wiper aux wiper/mtr purple os/roof
j/box aus Ign fuse j/box pink b/head
various
item earth black various
Below is a basic A7 diagram from about 1932, but with 1950s headlight wiring colours.
This comprehensive diagram is more accurate, but gets a bit complicated!
This lets you look up a colour of cable, and see what it connects to.
Black Many things earthed a nearby body earth point.
Yellow/black Power from starter motor to masterswitch
Yellow/black From masterswitch to ammeter
Brown From the ammeter, via a fuse to electronic voltage regulator
White/purple From the ammeter to Ignition switch , A.
White/purple From ignition switch , A. to
Non-ignition ‘aux’ fuse
White/purple From non-ign fuse link to Lights fuse
White/purple from Lights fuse Light switch
White From ignition switch, IG Ignition fuse
White From ignition switch, IG Coil (not fused)
White/black coil distributor
Red From switch on steering wheel to junction box under bonnet and
to
Offside indicators
Red From light switch, via fuse to junction box in car and to all Sidelights
Blue Light switch, via fuse to Dipswitch
Blue/white From dipswitch Main beam headlight via junction box in car
Blue/red From dipswitch Dipped headlight via junction box in car
Ignition fuse Brake-light switch Green/purple
Brake-light switch Brake-lights Green/purple
Re ind os j/box Os rear red Os roof
Fr ind ns j/box ns n/plate red Os wing
Re ind ns j/box ns rear red ns roof
j/box f/box j/box red b/head
Stop lts St/lt sw Ns st lt Gr/purp Ns roof
Os st lt Ns st lt Os st lt Gr/purp boot
Centre st lt ns st lt cent st lt Gr/purp boot
Centre tail Ns tail cent st lt red boot
h/light h/l sw f/box blue dash
h/light f/box Dip sw blue In car
h/light main Dip sw j/box Blu/wh In car
h/light dip Dip sw j/box Blu/red In car
h/light main j/box Os h/lt Blu/wh Os wing
h/light main j/box Ns h/lt Blu/wh Ns wing
h/light dip j/box Os h/lt Blu/red Os wing
h/light dip j/box Ns h/lt Blu/red Ns wing
coil Ign sw coil wh Os wing
coil coil dist Wh blk Os wing
Dynamo D dynamo f/box yellow Os wing
Dynamo D f/box reg yellow b/head
Dynamo F dynamo fuse green Os wing
Dynamo F fuse reg green In reg
Horn sw j/box horn yellow X BULK
Horn horn aux purple X BULK
wiper aux w/mtr purple os/roof
j/box aus Ign fuse j/box pink b/head
various
item earth black various
This car is wired NEGATIVE earth.
It always has been negative earth,
positive earth was not introduced until 1936.
item Colour of wire Position of wires
Negative battery lead to the starter motor casing, and to the body, bolted to the battery box.
Black
The positive battery lead is connected to the starter motor terminal. Black
Everything else is earthed to a nearby body earth point. Black
Everything is powered by a thick wire from the starter motor which goes
to
the isolator switch behind the dashboard
Yellow/black
This thick wire continues from the isolator switch. to the ammeter Yellow/black
From the second terminal of the ammeter to electronic voltage regulator Brown
From the second terminal of the ammeter to Ignition switch , A. White/purple
From ignition switch , A. to Non-ignition fuse White/purple
Linked from non-ignition fuse to Lighting fuse White/purple
from Lighting fuse to Light switch White/purple
From Light switch to Dipswitch via fuse Blue
From dipswitch to Main beam headlight via junction box in car Blue/white
From dipswitch to Dipped headlight via junction box in car Blue/red
From light switch to Fuse, then Sidelights via junction box in car Red
All sidelight wiring from junction box to Front sidelights Red
All sidelight wiring from junction box Through o/s roof and across in boot Red
NOTE…
SIDELIGHTS AND
offside INDICATORS
ARE BOTH RED
RED
From ignition switch, IG to Ignition fuse White
From ignition switch, IG to coil White
coil to distributor White/black
Ignition fuse to Brake-light switch Green/
purple
Brake-light switch to Brake-lights Green/
purple
Junction
Front indicator offside Underbonnet
junction box Os wing red Os wing
Rear indicator offside Underbonnet
junction box Os rear red Os roof
Front indicator
nearside Underbonnet
junction box ns n/plate red Os wing
Rear indicator nearside Underbonnet
junction box ns rear red nearside roof
j/box f/box j/box red b/head
Brake lights brakelight switch Nearsides st lt Green/
purple Nearside roof
Offside Brake lights to nearside Brake lights Os st lt Gr/purp boot
Centre st lt ns st lt cent st lt Gr/purp boot
Centre tail Ns tail cent st lt red boot
h/light h/l sw f/box blue dash
h/light f/box Dip sw blue In car
h/light main Dip sw j/box Blu/wh In car
h/light dip Dip sw j/box Blu/red In car
h/light main j/box Os h/lt Blu/wh Os wing
h/light main j/box Ns h/lt Blu/wh Ns wing
h/light dip j/box Os h/lt Blu/red Os wing
h/light dip j/box Ns h/lt Blu/red Ns wing
coil Ign sw coil wh Os wing
coil coil dist Wh blk Os wing
Dynamo D dynamo f/box yellow Os wing
Dynamo D f/box reg yellow b/head
Dynamo F dynamo fuse green Os wing
Dynamo F fuse reg green In reg
Horn sw j/box horn yellow X BULK
Horn horn aux purple X BULK
wiper aux wiper/mtr purple os/roof
j/box aus Ign fuse j/box pink b/head
various
item earth black various
Below is a basic A7 diagram from about 1932, but with 1950s headlight wiring colours.
This comprehensive diagram is more accurate, but gets a bit complicated!
This lets you look up a colour of cable, and see what it connects to.
Black Many things earthed a nearby body earth point.
Yellow/black Power from starter motor to masterswitch
Yellow/black From masterswitch to ammeter
Brown From the ammeter, via a fuse to electronic voltage regulator
White/purple From the ammeter to Ignition switch , A.
White/purple From ignition switch , A. to
Non-ignition ‘aux’ fuse
White/purple From non-ign fuse link to Lights fuse
White/purple from Lights fuse Light switch
White From ignition switch, IG Ignition fuse
White From ignition switch, IG Coil (not fused)
White/black coil distributor
Red From switch on steering wheel to junction box under bonnet and
to
Offside indicators
Red From light switch, via fuse to junction box in car and to all Sidelights
Blue Light switch, via fuse to Dipswitch
Blue/white From dipswitch Main beam headlight via junction box in car
Blue/red From dipswitch Dipped headlight via junction box in car
Ignition fuse Brake-light switch Green/purple
Brake-light switch Brake-lights Green/purple
Re ind os j/box Os rear red Os roof
Fr ind ns j/box ns n/plate red Os wing
Re ind ns j/box ns rear red ns roof
j/box f/box j/box red b/head
Stop lts St/lt sw Ns st lt Gr/purp Ns roof
Os st lt Ns st lt Os st lt Gr/purp boot
Centre st lt ns st lt cent st lt Gr/purp boot
Centre tail Ns tail cent st lt red boot
h/light h/l sw f/box blue dash
h/light f/box Dip sw blue In car
h/light main Dip sw j/box Blu/wh In car
h/light dip Dip sw j/box Blu/red In car
h/light main j/box Os h/lt Blu/wh Os wing
h/light main j/box Ns h/lt Blu/wh Ns wing
h/light dip j/box Os h/lt Blu/red Os wing
h/light dip j/box Ns h/lt Blu/red Ns wing
coil Ign sw coil wh Os wing
coil coil dist Wh blk Os wing
Dynamo D dynamo f/box yellow Os wing
Dynamo D f/box reg yellow b/head
Dynamo F dynamo fuse green Os wing
Dynamo F fuse reg green In reg
Horn sw j/box horn yellow X BULK
Horn horn aux purple X BULK
wiper aux w/mtr purple os/roof
j/box aus Ign fuse j/box pink b/head
various
item earth black various