Parking lights not working. Painless harness

[POPO1984]

I have a painless harness installed. I am having issues with the parking lamps not coming on. I understand that the bulb itself grounds through the housing (i think). I have power coming to the blue wire side of the connection which is the turn signal but the brown wire which is #927 I have no power coming too it. This wire comes from the headlight switch. Just thinking now would it matter in the switch itself was mounted or grounded? What actually makes the parking lamps come on?

Also does anyone know what the upper relay on the fuse box is for. I do have painless no load relays in each relay receptacle.

[_Ogre]

i believe 72 was the last year that had 2 hot wires feeding the headlight switch
normally there would have been an orange wire feeding the dome, brake switch and marker lights from the fuse panel
i found a picture that vet vette posted of the headlight switch diagram
the red wire feeds only the headlights and dash lights,
the orange wire is actually a hot from the fuse panel that also feeds brake/dome/marker

what i would do is feed from your brake light hot to the orange wire connection on the headlight switch
this gets the load for all other lights off your headlight circuit
you can jump the red to the orange but that might overload your headlight circuit when you least expect it



and a 2nd pic from vv, similar switch red for headlight, orange for all other lights

[VetteVet]

I'm assuming we're talking about the 72 in your signature and not an 84 in your user name. Also it's a GMC if I'm correct.

Going on that assumption.

Yes the bulbs are grounded through the housing. If your turns work then the housings are grounded, or they are getting ground through the side markers/turn lights. Easy to check, just jumper the brown wire at the headlight switch and see if they come on. It won't hurt to clean the housings and the mounts. The sockets are rubber mounted so the housing for the light has to be connected to the core support.

The brown wire is the power source for newer trucks but the 67 to 72 front lights use a purple(violet) wire for the parking lights in the front and they feed from the firewall block with the tan and light green headlight lights. The brown wire from the headlight switch goes into the cab side of the block and the purple(violet) wire comes out on the engine side of the block.

The back wires are brown and feed through the firewall connection just behind the distributor, along with the rear yellow and dark green turn wires, and the light green backup lights. See the first diagram.

It also shows the dome light connection Orange wire and white wire. The orange wire is constant hot when the battery is connected. The white wire is the ground and it connects to the door switches and the headlight switch, to turn on whenever the doors are opened, or when the headlight knob is turned clockwise. SO YES THE HEADLIGHT SWITCH NEEDS TO BE GROUNDED THROUGH THE DASH. If your dome light works through it then it's grounded.


Here is the diagram for the rear lights.



Here is the diagram showing the headlight switch and the brown wires for the parking lights. Ignore the arrows on the ignition switch at the top, they show the brown accessory wire to the fuse block and the resistance wire to the external regulator.



This diagram shows the brown wires going to the connector and to the firewall block. The firewall block is on the lower left and there are more than one brown wires going into it. The one for the front lights is just below the green wires from the dimmer switch.



On the engine side of the firewall block the brown wire becomes the purple
(violet) wire for the parking lights. This violet wire may have changed to a brown wire when the factory actually starter putting the marker lights in the fenders, 1969 and up. This diagram shows the engine side of the firewall block. The violet wire is on the far left below the tan and green headlight wires. It may be brown on your truck or something else if you have a painless fuse block mounted there.




This one shows the circuit for the trucks with marker lights and turn signal lights. My 67 does not have those lights so maybe your 72 does have the brown wires instead of the violet wires.



Now the disclaimer on all this is that if your painless harness supplied an new fuse block then your wiring may be different than factory stock. They make all kinds of harnesses for out trucks to include, HEI ignition, headlight relays, alternator conversions etc.

The relay you are asking about might be The TCS relay or the AC relay. It's hard to say without a picture.

[VetteVet]

Here is the headlight switch that you may have although you should have the one that Qgre posted.





Here is the stock fuse panel with the TCS relay just above. The horn relay is just above that. TCS stands for transmission controlled spark and was a pathetic attempt from the factory to help emissions. Most guys just disconnected the wiring and ran without it.

[Apachemike]

Guess the best question is which headlight switch do you have and how do you have it wired? Picture would be awesome

[POPO1984]

Sorry the truck is a 72 chevy. I am using the factory ac Delco switch. I just don't understand how the blinkers work but the parking lights dont.

[VetteVet]

It's quite simple really. The parking lights operate off the headlight switch and the turn signals work off the turn signal switch. They are on entirely different circuits. The parking lights work off the brown wire and if you aren't getting power to the brown wire then they aren't going to work.
As I detailed above, the front and rear parking lights are powered by different brown wires so the rear lights may work and the fronts may not.

It's also true that the front and rear turn signals work off the same circuit so all four including the marker lights are powered by the same wire. It's a purple wire in the center of the steering column connector.

If you have no power on the brown wire then it stands to reason that they are not going to work.

[POPO1984]

So at what position should my headlight switch be in order for the parking lamps to come on. I want to make sure that I'm testing for power with the switch in the right position.

Actually I was asking about the two relays that are on the painless fuse panel itself. I think I have it figured out that the top relay is for hazards and the bottom is for the blinkers.

[Apachemike]

Parking lamps should come on in both positions. I wish I took pictures because I just did this.

[VetteVet]

If you're going to jump the brown parking light wire to then it doesn't matter because you'll bypass the headlight switch and put power directly to the parking lights. Mike is correct, they are supposed to come on in the first and second positions.

Where are you going to access the brown wire to jump it to power the parking lights? You have to be careful because there are several brown wires in the harness. The headlight switch at 927 would be the best place.

It is going to be real hard for us to help you on the relays on the fuse panel without a picture. Don't you have a manual from painless or a lettering below the relays to tell what they are?

[_Ogre]

vettevet: was my ''i believe 72 was the last year that had 2 hot wires feeding the headlight switch'' assumption wrong?

[VetteVet]

I'll have to look at the 73 and up diagrams and see, but the red power wire and the orange wire from the fuse panel are the two hot wires to the head light switch. The 2nd and 3rd diagrams above show that.

[POPO1984]

Well after playing with it last night I noticed that my side marks were staying on after turning the switch off even with the truck off. I could wiggle the switch and They would go off so I plugged in my old switch and everything now works perfect. I'm returning the new switch and I'll just stick with the old one until it goes out on me. The new one was an ac delco switch by the way.

[Longhornss]

If you have the painless harness in your truck the relay mounted to the fuse pannel is likely the horn relay.
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