Jaguar Repair/1969 e-type ignition
Car is a FHC which originally came with A/C which has been removed. About 5 years back I up-graded the alternator to a Bosch which eliminated the original voltage regulator.
There is a double white wire connected to one contact on the ignition switch. Can you tell me where it goes? The wiring diagram only shows one (1) white wire coming from the starter switch and running to the #6 fuse.
The wiring diagram also shows a White/yellow wire from the starter to a relay at C2. This relay is not there. The car has been running like this since I bought it in 1988.
I only recently found out about the US verses British fuses. I changed all fuses to 20 amp and one 25 amp and then all the problems started. I keep losing #6 fuse. All others continue to be OK.
It would be unwise to worry about your car matching any wiring diagram because you already know some changes have been made by privious owners. Even when I worked in the dealerships I often received cars that had many electrical changes so I always had to look at the function of each section rather then worry about it matching one of the several diagrams.
The original Lucas wiring did keep close to the color codes that Lucas used on all British cars. Brown wires were used as power wires and usually were not fused. White wires were used as Ignition-on power wires and were usually only used around the Ignition system on the power side of the coil. Black wires were ground wires. So a white wire with a black stripe was used as the grounding wire for a coil. Green wires were accessary wires and thus the color of a strip on a green wire often told what it did. Like a green wire with a black stripe was a grounding wire for an accessary and a green with a brown strip was a powered accessary wire. Purple wires were unfused power wires for an accessary. Blue wires were for head lights and the white and red stripe on a blue wire were for each side. Red wires were usually small lights like instrument light wires.
If I had received your car and needed to trouble shoot an electrical problem I would check the function of the wire rather then the color since the car is known to be altered and is old.
For example, the ignition switch needs to power up the fuse box so you should confirm that a power (all the time) wire (usually a large brown wire) is at the ignition switch. Then disconnect the other wires on the switch and turn "ON" the switch and test which posts receive the power from the brown wire. (usually on pin #1) Or on column lock switches it would be a terminal labled ("30") The white wire you talk about to the #6 fuse (which also powers up #7 fuse also, is the power for all the white wires on those two fuses. On the steering lock switch the white wire is on pin ("15/54")
The white/ with yellow tracer wire from pin "3" or pin ("50") on the steering lock type goes to a starter relay (pin "W-1") to trigger the starter relay which in turn triggers the starter solenoid. The trouble with eliminating the starter relay and operating a starter solenoid directly is that it puts too much of a current load (amperage) on the starter / Ign switch.
If this relay has been removed, you should consider putting one in to take the load off of the ignition / starter switch. (only Lucas relays use the letters "W-1, W-2, C-1 and C-2". The relays the rest of the world uses are labled "85 & 86" for the electro magnet that triggers the relay and they use "30/51 and 87" as the power and output pins.
Trace your wires back form the starter solenoid to see where it goes. Someone may have either just moved the Lucas relay or they may have eliminated it (bad news).
You should also look at the ignition system as many cars end up with aftermarket ignition systems when they get older.
When I would get any car that was blowing a fuse I would remove all the output wires from that fuse and test each one. One at a time to find which circuit is causing the fuse to blow. If it only happens at times you may have to remove all the output wires and temperaraly put an inline fuse on each wire to find the one that is doing it and then trace that circuit only to its load (item that it operates).