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Wiring

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Bob Claffie

Bob Claffie

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The PO of my new/old AH 100/6 stripped out the old wiring harness and reconnected about 25% of the new one. Since I have yet to receive the restoration manuals I ordered thought I'd ask which book has the most useful information on routing and connecting. I have a wire diag but the colors of the wires in the braided harness leave something to be desired. I see "extra" wires where there appears to be no device to connect them to and likewise some equipment that doesn't seem to have any wires nearby. I hate the idea of taking the harness apart just so I can physically trace the individual wires. Thanks, Bob
 
Hi Bob,
When I installed my harness, I sat down on the floor with the harness, wiring diagram and an ohm meter. Oh, and some good music! I started at the dash area, identified a wire, and used the meter to make sure I found where it popped out again. Then I labeled both ends, and so on. This way, you don’t need to rip open the braiding. I wonder if the PO routed the harness incorrectly so things don’t line up, or maybe you have the wrong harness? I’m not particularly familiar with the 100/6, what components don’t have wires near them?
 
Greg: No wires near the wiper motor, two extra wires down below the generator. Lots of "extra" wires at the firewall near the OD relays. Since I have all winter I could take the whole thing out and use your method but I expect that most of the things already wired up are correct and I don't want to reinvent the wheel. On top of that my non-adjustable steering wheel doesn't have a control head (+/-$900) so I'm going to have to jury rig directionals and a horn. I'm sure the purists will moan but I'm trying to build a AH driver on an MG budget. Bob
 
Hi Bob,
The wiper motor wires are a “mini harness” that should have come with the main wiring harness, maybe in a box somewhere? Green, green/black, black wires in a black cloth sleeve. They attach to the harness in the engine compartment above the steering column. See attached. Under the generator could be a couple of things. The color of the wires would help a lot.
147063-wiperwire.jpg
 
Greg, Yes, I do have a group of wires in that location but no extension to get them into the cockpit. The wires under the generator (and continue from the generator) harness are black and blue with red or maybe purple. Can't get my head in there close to be sure. Biggest question I have is: the tail end of the harness to the rear of the car (fuel pump, fuel gauge, lighting circuits, not that small lighting mini-harness) is laying on the driver side floor. I'm pretty sure this should run under the car, or in the tunnel, but have no clue how to get it there. Bob
 
Bob,

Working from memory (so all the details might not be exact!)..the rear harness plugs into the main harness in between the steering column and oil pressure hard line (Greg's picture shows the general area). It then drops straight down through a smallish bracket/grommet and continues straight down on the outside of the footwell heatshield. This is the heatshield closest to the tunnel opening. Note, there is a wire clip used on one of the heatshield mounting bolts. The harness then follows the left main rail back to the rear end tunnel (look for the wire clip mounting holes)and goes up the vertical wall. One finger branches off right to the fuel pump. The rest goes up and across the rear end tunnel and back down the trunk bulkhead. There is a grommet on the left side of the trunk bulkhead where the harness continues for the rear lights and license plate lamp. And a smaller grommet just below it for the gas tank sender wire. Anyway .. that's the general idea.

Cheers,
John
 
Hi Bob,
The blue/red wire is for headlights, purple is the horn. You might try calling British Wiring to get the bits you're missing. Do you have the little harness for the headlight dimmer switch?
The only thing I’ll add to John’s routing description is: On my car (a late BJ8) the rear harness is wire clipped to the axle bump stop. This photo shows the general routing once the harness leaves the framerail.
147623-harness.jpg
 
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