B1B Wiring Harness Diagram Notes From David Erb     (rev. 07 dte)

This harness is very easy to build. I made mine in about four hours. It is inexpensive to make. The terminal ends and bullet connectors actually cost more than the wire. The B1B circuitry for the electric system is very basic, and consists of only about 30 separate pieces of wire. The electrical schematic for the circuits can be found in the shop manual and in the Dodge Pilothouse website archival information.
There are four very short wires you need to note when building this harness. Wire number 2 connects the light switch to the ammeter. Wire number 3 runs from the ammeter to the ignition switch. Wire number 6 connects the fuel gauge to the ignition switch. Another very short wire connects the headlight switch to the panel switch, number 12 in the detail on page 1. The drawing shows these wires wrapped into the harness, but this is optional and is not necessary. All these components sit in the dash within a few inches of each other.
Page 1 and 2 of the drawings show the Main Harness that serves the dash and engine compartment. Page 3 illustrates the Rear Body Harness. You need weatherproof bullet-type connectors to join the two harnesses professionally. They are near the steering box area. You will also need similar connectors to join the tail and park lights to their harnesses. Without turn signals you will need nine of these connectors. Turn signals will require an additional five connectors.
I have shown the Rear Body Harness drawing as the correct arrangement for applications where turn signals are used, on page 3. If you are not using turn signals, you do not need wires number 25 and 26. Just run wire number 24 from the brake light switch back to each tail light for the brake lights. Likewise, on the page 1 drawing you may eliminate all the optional wires shown for the turn signal switch application.
When you build your harness, it is helpful to first make number labels for each wire. I used a computer mail label maker. You can alternately buy a few sheets of labels and use these to number each wire at both ends before you wrap it into the harness with tape. If you follow this practice, you will never have to get out the ohmmeter to find which wires go where. Ask me how I know . . . . . . 
I found that when wrapping the loom, it works best to wrap a rag around one end and pinch it in a vise. Then get a helper to hold the assembly taunt while you wrap it with tape. Best to use a good quality vinyl tape product here – this is not a logical place to scrimp. Optionally, you may wish to use vinyl covering over your taped harness after it is finished. Several products and colors are available.
Build the complete harness before you install the terminal ends. These can be put on after the assembly is completed. I suggest using uninsulated terminals that are soldered and insulated with heat shrink tubing. This method is far superior to using crimped terminals. I found uninsulated terminals, wire and harness connectors at Sherco Auto Supply, Margate, FL, 954-975-0012 or at   www.sherco-auto.com. They also carry the weatherproof bullet connectors necessary to join the rear body harness to the main loom and for connecting tail and parking lights to their respective looms. Their prices are very reasonable.
Wal-Mart sells a refillable pocket torch for $12 that uses butane lighter fuel. It is just a little larger than a disposable lighter, and is instant on-off. This is the perfect tool to use for heat shrink tubing and soldering. Please don’t use it under the dash – it can start fires.
When you install your new harness, it must go through the firewall from the dash side. Work it through carefully until you have the horn and regulator wires through, then it is in the correct spot.  It may be helpful to connect the ignition switch and the head and panel light switches to your harness as soon as you have soldered your terminal ends in place, in order to keep things more organized.
On the ignition switch, the tallest of the three terminals gets only one wire, while the other two each have several wires on them. The factory used one nut between each wire terminal, and just stacked them up. On the panel switch, the single wire goes on the right side terminal and the three-gang connector goes on the left side, terminals facing upward in the dash. The single wire goes on the right side ammeter post as it sits in the dash, and the remaining wires all go on the left side post.