66 C10 AAC Wiring Questions
 

Starting to test out the circuits;
Headlights shift between low and high which is great
Issue is the Bright Light on the cluster comes on either way

What is wrong?

Re: 66 C10 AAC Wiring Question - Hi Beam Lite
 

It sounds like the hi beam indicator is wired before the dimmer switch and it should be after the switch on the hi circuit. It sounds like it is wired to the light switch and is on when the lights are on. As a side note where is the hi beam light in the cluster? My truck never lights up and I haven't really looked for it.

Re: 66 C10 AAC Wiring Question - Hi Beam Lite
 

This

Re: 66 C10 AAC Wiring Question - Hi Beam Lite
 

Thank you, the DPO of my truck cut the wires off at the fuse box and rewired everything under the dash with one color of wire, white, and spiced everything together, a total nightmare.

66 c10 AAC Wiring - Brake Lights
 

Ok
Another issue

Turn headlights on....brake lights come on
No bearing on the pedal being depressed or not

Re: 66 c10 AAC Wiring - Brake Lights
 

Just a guess, but I'd say off hand that you didnt wire it correctly. :)

Re: 66 C10 AAC Wiring Question - Hi Beam Lite
 

On the wiring everything is new using AAC Harnesses.

Everything is labeled; plug and play
So what could this be??

Re: 66 c10 AAC Wiring - Brake Lights
 

Has to be something else
AAC prelabeled harnesses

66 c10 AAC Wiring - Front Park/Turn Lights
 

In what situations should these turn and off;

Do these only come on with turn signal switch engaged?
I tried that and nothing

Re: 66 C10 AAC Wiring Question - Hi Beam Lite
 

What did AAC say?

Re: 66 C10 AAC Wiring Question - Hi Beam Lite
 

I haven’t asked them
Assumed someone here could help

Re: 66 C10 AAC Wiring Questions
 

The hi beam wiring would probably wire into the dimmer switch and be on the hi beam side of the switch so it would only be hot when the hi beams were on. Perhaps you wired it to the hot going to the switch which would light every time you turned the lights on.

Re: 66 C10 AAC Wiring Questions
 

Hhm ok
So another question then.

Does the key have to be engaged for the headlights to turn on?
Right now, i can turn them on wo the key.
Which means its tied to the battery and not the ignition Switch? Yes?
Is this correct ?? or have any bearing on the issues above?

Re: 66 C10 AAC Wiring Questions
 

Im using AAC harness as well. Did a complete rewire....My HL's activate with key off.
About your brake lights coming on with your HL's, are you sure they are your brake lights and not just your taillights? When they are on, and you activate the brake, what happens? Brighter lights or no change? If it is truly your brake lights, then maybe they are simply reversed at the tailight socket or wherever you spliced them together. I did that by accident with my rewire. Just swapped the 2 wires and it worked.

Re: 66 C10 AAC Wiring Questions
 

See if this is correct
May not be
I have 3 brown wires labeled “park lights”.
Do i have it correct or do all 3 wires get tied together??
And slot does it go into?

I do see now i ran the double brown to front parking lights then split side to side

The single brown i ran to the rear lights

If i reverse these at the light switch would this correct my issue

When you look at the AAC diagram i just noticed they have tail light lead and the park light lead reversed in order when u follow the diagram

I will swap these tomorrow and see

Side note. On the hi/li beam switch i still dont see what went wrong; suggestions on this;

Re: 66 C10 AAC Wiring Questions
 

The single brown wire on the rt is parking lamps are on in front stay on when headlights are on, factory I think was they were off when headlights were on. Split the 2 brown wires 1 front 1 rear for parking lights. don't use the single wire, unless you want them on in front. Brake wire should be separate color, Light blue. Good ground wires from body to frame and motor? What number is this kit?

Re: 66 C10 AAC Wiring Questions
 

Kit 500560
My brake wires are brown, just like the parking.

Lite blue is 3rd parking which im not using
Dk green is right
Yellow is left
Both combo with the brown

Re: 66 C10 AAC Wiring Questions
 

Attached is the '64 light schematic, the light switch harness doesn't look like it's matching your harness. Also, here's some things to try ...
1. Disconnect the light harness at the dimmer switch on the floor. Turn on the headlights, if the brights indicator is on, I'm betting a bulb behind the dash is in the wrong position.
2. Pull the orange wire at the brake lamp switch. If the brake lights are still on, double check the wiring.

Good luck and give updates as you go along.

Re: 66 C10 AAC Wiring Questions
 

The AAC Harness is definitely different then stock; the original schematic wont help. I checked the bright light location. It is correct

I will check the brake switch

Re: 66 C10 AAC Wiring Questions
 

Ok
I removed the floor dimmer harness from the switch And the brake switch harness

1.the head lights will not work and the hi beam indicator is off
2. Rear lights now act funny
A. Driver brake light bright
B. Passenger not on; ground issue? I can take a screw driver and touch the rear socket to one of the housing studs; light comes on very bright like driver side
C. I ohmed the rear wires and everything is ok
3. Could dimmer switch be bad even new with the kit?
4. Dimmer switch connector appears correct?
5. Parking lights i have hanging on the hood but not grounded yet; when I manually ground they turn on

Explain how the orange wire works on the brake switch?
Appears orange runs from fuse panel to switch and also powers the glove box light
the white wire is the 12v from the brake switch

Reminder. My column harness appears to resemble a 63 not like 66
I attached photo of column harness
In this order
Yellow, blue, white, dk blue, pink, purple
Black for horn
Grey for light

So is my steering column harness causing these issues?
Worth replacing?

Re: 66 C10 AAC Wiring Questions
 

Pressing the brake petal completes the brake light circuit. If one or both brake lights are on with the orange wire disconnected, recheck the wiring, something isn't right. Glove box could be part of the circuit if it's further upstream.

From the looks of the AAC diagram, the brights and the indicator split at the dimmer switch, one light green going to the lights wiring harness and the other to the dash lights. There shouldn't be any other intersecting wires, including at the harnesses, if there are, that should be the culprit. Also can't hurt to check continuity at the dimmer switch just to eliminate the possibility of it being bad.

I'm curious about the 2 brown wires coming out of the "Rear Tail Lamp" pin on the lights harness in the earlier photo. Where does each go, should there be only one wire coming out of it (can't tell from the diagram)?

To combat my ground issues at the bed, I cleaned away paint and rust in a small area on the frame and ran a 12 gauge wire from the frame to one of the bed studs. I also removed both tail light lenses and ran a 4" length of 14 or 16 gauge wire from the bed body to the tail light buckets. Haven't had a tail light issue since.

Re: 66 C10 AAC Wiring Questions
 

Single brown goes to the parking
Double brown to the rear tail; i will verify
I did ohm the wires to verify from light switch to each end run For both park and tail

Odd the LED brake lights are bright
No change with the brake switch plugged or unplugged

Best way to check continuity on dimmer switch?
The hi-lo beams work when engaged.

Re: 66 C10 AAC Wiring Questions
 

I also noted this
Back of light switch marked rear lights i have a double Brown park light;
1 of these goes to instrument harness but i didnt run anything from this. This note says park light for dimmer function; only used for digital dimmer

Re: 66 C10 AAC Wiring Questions
 

Most multimeters have a continuity function, it's the symbol below. Unlikely, but possible, the switch has the brights on in both positions and it's just turning the low beams on and off (in effect, you have brights and even brighter brights). If one of the poles has continuity when in both positions, you have your culprit.

For the tail lamps, if you haven't, I suggest disconnecting the harness under the rear bumper and take voltage readings from each of the wires as follows:
1. all lights off
2. all lights off and brakes on
3. running lights on and brakes off
4. running lights on and brakes on
5. running lights and head lights on and brakes off
6. running lights and head lights on and brakes on
If they all check out okay and you have decent voltage readings, you know the harness coming out of the cab is good, so the issue is definitely at the back half of the harness, which makes it much easier. If that's the case, most likely it's one of the following: the wiring and connections to the tail lights need to be reconfirmed; need better grounds to the tail lights; the LEDs don't want to work with 50+ year old technology.

As a side, I'm in the camp of not using LEDs on the truck, with a few exceptions. LEDs have requirements that don't mix with older vehicles, so they have a habit of doing some very odd things.

Re: 66 C10 AAC Wiring Questions
 

Update on the Hi Beam Bright light staying on—-
The green and ground were flipped backwards which caused current bleed over.
Lesson on this one
Pix to illustrate