The '61-'71 Dodge Truck Website
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Electrical System Information & Tech
This page is comprised of two sections; one which has a variety of downloadable (or printable) wiring diagrams and another which has some valuable tech tips. Both should be useful in troubleshooting and upgrading your Dodge Truck Electrical System.


Useful Tech Tips

How to R&R the Ignition Switch
With extreme use or frequent stop and go work, the ignition switch is one part of the vehicle that is highly prone to wear and tear. One noticible symptom of a worn switch (and not necessarily the cylinder) is that the truck will start fine but the gauges show nothing, the turn signals don't work and extra accessories (such as the radio) get no power. Another symptom is a grinding feeling when turning the key to start the truck. This is also characteristic of a worn switch.

Two components make up this portion of the vehicle's electrical system; the key cylinder and the switch itself. Both parts are available at NAPA stores if you can't find them elsewhere. Removal of the assembly consists of two simple steps. First, carefully remove the modular plastic plug from the back of the switch (performed behind the dash). Next, spin the chrome ring around the outside of the key cylinder in a counter-clockwise direction. You may need pliers to loosen the ring; if so, cover the jaws with a layer of thick tape to avoid marring the ring (Dodge dealers probably had/have a special tool for these but this procedure works fine). Drop the switch assembly out from the dash and grab your keys--you'll need them to release the cylinder from the switch. Once ready to separate the switch from the keyed cylinder, simply insert your ignition key and turn it as if you were to turn the truck on. Now, pull the larger switch body away from your key and the two should release.

You'll also need your key (new or old) to put the switch body and key cylinder back together. Insert your ignition key into the cylinder and turn it; you'll notice that a spring loaded detent will lower itself allowing you to place the cylinder back into the switch body. Place the assembly back in its proper hole in the dash, then screw the chrome ring back onto the end of the protruding switch. When the assembly is secure, re-attach the modular electrical plug at the back of the switch.

Ground Problems and Running Lights
One problem that kept me grieving for about a month (right around the time I wanted to install my thrid brake light) was a ground problem with my rear brake lights. Before I figured the problem out, all I knew is that the rear lights didn't work (running light or brake circuit) and the turn signal indicators on the dash panel would show little or no response to turning the left/right turn signal on. The front lights were working fine, and responded whenever the turn signal decided to blink with a seven to eight second delay (way too long of a delay, obvoiusly). Every once in a while or when I would turn a corner the turn signal would start to work normally with the proper delay between blinks.

After tracing all the wires from the turn signal switch to the back of the truck (using nothing more than a test light), I realized that current was flowing but the lights still weren't getting the juice. Even though I sanded around the screw holes and flanges of the light housing with sandpaper, a good ground was not present at either side of the truck. To fix the problem, I prepared two wires that were long enough to reach from the metal light housing down to the frame. Onto each end of both wires I crimped a soliderless connector that would accept a pop rivet. Holes were drilled on both the light housing and the truck's frame and pop rivets were fastened through the connector ends of the wires to hold them onto the frame and each housing.

Generally speaking, since the truck bed is just a big hunk of metal the procedure of sanding the contact points of the bed and housings should have worked. In my case, the bed (for some reason) does not have good metal to metal contact with the frame. Wood blocks were used as spacers to mount the bed onto my truck but metal bolts fasten the bed to the frame. Strange? Who cares, they work now!

Grounds are required for direct current devices (i.e. automobiles) because the flow of electrons must have a return path to the source (battery). Without the return path, the electrical pressure (voltage) cannot overcome the resistance to electron flow and thus nothing happens with the non-grounded device.

How to R&R the Brake Light Switch
Another frequently worn electrical part is the brake light switch. This small part has plastic which becomes brittle over time, causing the switch to not trigger or get hung up on itself. A replacement part is available at NAPA stores, but I found that the part they gave me required some modification before getting it to install properly.

First things first. DON'T THROW OUT YOUR OLD SWITCH! You may need it to adapt the new switch to your truck. This may not be true for all truck years or models, but on my truck the little switch has a threaded portion which allows it to be fastened through a hole with a thin sheetmetal "quick nut". The new NAPA part I got was nearly identical to the old version but it did not have the threaded part. Instead, it had a metal clip which may be used for attachment on other Dodge Truck models (if you can clear this up, let me know). If you find yourself in the same situation, don't worry. Here's how you you remedy the situation using the old part and the almost correct NAPA part. Now, prepare to destroy the old switch (it took some guts on my part because I wasn't sure that I could do this and a replacement part would be days or weeks away). This is necessary because you need the threaded portion to be added to the new part (kinda like other stuff on these trucks, just replace the bad components and reuse the good). What I did to accomplish this is not really scientific, just break all the plastic and innards of the old switch that you can until the center is clear for a big drill bit. Once nearly everything has been busted off but the threads and some plastic, use a drill and the large bit to carefully drill out the rest of the plastic. DO THIS WITH CAUTION - hurried drilling can destroy the threaded metal piece. You may want to hold the busted apparatus with a pair of good pliers that have thick tape applied to the jaws. Do this by holding the part by the threads with the protected jaws of your pliers. If you did this right, all the plastic should have been removed by the drill bit and all that is left is the threaded metal ring.

The new NAPA part will gladly accept the threaded ring in the same position as the old switch. On mine, the ring went on too far (I think the new switch is a little shorter than the old) and required that the switch be adjusted all the way forward. Even at this position the switch doesn't always get pushed by the pedal and my brake lights occasionally stay on. I haven't done this, but try using some hot glue or super glue gel to make the threads fit a little ways back on the switch if you have the same problem.

Turn Signal Cams
A frequent pet peeve with Dodge Truck owners is that one or both turn signals do not cancel. This problem is caused by a broken turn signal cam and can be easily remedied with the proper part. Two types exist for `61-`68 Dodge Pickups, one is for the white steering wheel with chrome horn ring while the other is for the plain jane steeering wheel and column with a horn button in the center. The reason there is two types is that there are also two types of turn signal switches for these columns, one for each type of steering wheel. For `69-`71, I am guessing that the turn signal cam is the same as the simple horn button type of cam just because Dodge liked to keep many things the same over the eleven year run of these trucks. Let me know if you have seen otherwise.

I can't remember what the name of the company that reproduces the turn signal cams is but I can tell you that one part number is S-9 and the other is S-12. The fundamental difference between the switches is that the switch with the horn ring just has a simple plastic part that cancels the turn signal. For those of us with the more common horn button steering wheel, we have more work to do to replace ours. The switch for the more common horn button wheel/column has integrated wires and connectors which allow the signal to operate and cancel with one part. To change either part one must first remove the press fit washer from the cam and then worry about the other stuff. Just swap the cam if you have the simpler setup. Solidering and splicing is required for the rest of us. Nonetheless, the time spent is well worth it considering that you won't have to cancel your turn signals anymore!

Using the Buss Bar as a Power Source
A slick little electrical device that was OEM installed your truck is called the buss bar. This little metal post with eight rectangular male quick connections allows you to add nearly anything electrical you need to power. Energized only when the ignition is on, this source is great for the main power of a cassette deck, a tachometer or even an electric choke unit on a new four barrel carb. The "bar" of terminals is located on the back of the gauge panel between the ammeter and fuel gauges. Therefore, if you've got a `61-`71 Dodge Pickup (from what I can tell, A-100's and A-108's didn't have buss bars) and want to add something electronic that is only energized when the truck is "on" then just tap into the buss bar! Note: Be sure to add an inline fuse to all connections made to the buss bar, as it is not a fused power source.

Wiring Diagrams
All of the wiring diagrams listed below have been scanned in at their original size (72dpi) and should make good printouts on two pages of standard 8.5"x11" paper. To make the wiring diagram "fit together" simply trim one of the two printed pages so that the lines from the diagram match those on the other page. Also, these should print out perfectly without having to change your print setup to "Landscape" page orientation unless otherwise noted. Just click print!
`64-`70 A-series Compact Truck Wiring Diagrams
Image: 64_awire.jpgWiring diagram for 1964 A-100 Vans and Pickups. (Diagram Courtesy of Dave Cirillo)
Wiring diagram for 1965 A-100 Vans and Pickups.
Wiring diagram for 1966 A-100 Vans and Pickups.
Wiring diagram for 1967 A-100/A-108 Vans and A-100 Pickups.
Wiring diagram for 1968 A-100/A-108 Vans and A-100 Pickups.
Wiring diagram for 1969 A-100/A-108 Vans and A-100 Pickups.
Wiring diagram for 1970 A-100/A-108 Vans and A-100 Pickups.
`61-`71 Dodge Pickup Wiring Diagrams
Wiring Diagram for 1961 Dodge Light Duty Pickups. (Diagram Courtesy of Dave Cirillo)
Wiring Diagram for 1962 thru Mid-1965 Dodge Light Duty Pickups. (Diagram Courtesy of Dave Cirillo)
Turn Signal and Brake Light Wiring Diagram for 1961 thru Mid-1965 Dodge Light Duty Pickups. It is recommended that you download (or print) this along with your `61-`65 Wiring Diagram. (Diagram Courtesy of Dave Cirillo)
Wiring Diagram for 1965 Dodge Light Duty Pickups. From `65 Dodge Truck Service Manual. May be useful for `64 thru `66 pickup trucks as well. Compare colors with you truck's wiring to verify. Print this diagram using "LANDSCAPE" paper orientation.
Wiring Diagram for 1966 Dodge Light Duty Pickups. Print using "LANDSCAPE" paper orientation.
Wiring Diagram for 1967 Dodge Light Duty Pickups. Print using "LANDSCAPE" paper orientation.
Wiring Diagram for 1968 Dodge Light Duty Pickups. Print using "LANDSCAPE" paper orientation.
Wiring Diagram for 1969 Dodge D or W-Series 1/2 & 3/4 Ton Pickups. Print using "LANDSCAPE" paper orientation.
Wiring Diagram for 1970 Dodge D or W-Series 1/2 & 3/4 Ton Pickups. Print using "LANDSCAPE" paper orientation.
Wiring Diagram for 1971 Dodge D or W-Series 1/2 & 3/4 Ton Pickups. Print using "LANDSCAPE" paper orientation.

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