70 brake light issue

[psuedopimp]

Ok sometimes I have them and sometimes I don't. Frustrating! I pulled the switch and used my ohm meter to check connectivity. Beeped when button released and was quiet when button was pushed. So I am assuming switch is good. I also checked voltage where switch plugs into 12 v so now in at a loss. Turn signal and tail lights both work.

I also tried a jumper wire where the brake light switch is supposed to go. Still nothing.

Any ideas?
Posted via Mobile Device

[VetteVet]

If you jumped the orange wire which is the power wire and the white wire which is the brake light light you should have brake lights. You have also checked the continuity on the brake light switch and it is good. Either you have intermittent power on the orange wire or the white wire is not making good contact to the turn signal switch to power the green and yellow wires that share the current to the turns and brake lights. You might not have a good connection at the steering column connector.

[psuedopimp]

Thanks. That gives me another place to look! I appreciate it
Posted via Mobile Device

[psuedopimp]

Ok so I took the steering wheel off and looked at the wires there and every thing was sturdy I guess for lack of a better term! Then after all tht was back together I found the horseshoe connection under the dash. I checked the white wire. 12 v. I then checked the black wire it went to after the connection and that had 12 v.

Is there other wires I need to check? Now I'm lost!
Posted via Mobile Device

[VetteVet]

Originally Posted by psuedopimp

Ok so I took the steering wheel off and looked at the wires there and every thing was sturdy I guess for lack of a better term! Then after all tht was back together I found the horseshoe connection under the dash. I checked the white wire. 12 v. I then checked the black wire it went to after the connection and that had 12 v.

Is there other wires I need to check? Now I'm lost!
Posted via Mobile Device

Well that's interesting. The black wire is shown as a white wire in the factory diagram and the only black wire from the connector is going to the horn button in the steering wheel. I wouldn't put it past the factory to use a different color to complete the harness as long as they knew what it was going to.

it is possible that the orange wire connection at the fuse panel is intermittent or that the fuse for the Stop/Turn/Tail is not making a good connection. The harness to the rear lights is in the firewall behind the distributor and there is another one about halfway down the frame. Bad connections in either one of these would affect the lights. it should affect the tails and turns as well though if that were the case.

The light sockets for the rear lights may not be grounded well also, but again this would affect the other lights too.

The next time they quit working try moving the turn signal lever back and forth and see if they begin working again. If they do then you can suspect the TS switch.

Here's a couple of diagrams to show the wiring paths.

Here's the fuse box side of the harness with the connector on the upper right. The brake switch is just to the left of it. You can follow the orange power wire from the stoplight switch down to the fuse panel. Ignore any arrows.




Here is the harness to the steering column

[psuedopimp]

thanks for your response! i figured for 7 bucks i would switch out the switch and hopefully something would work.. nothing.... so i was going to cruise it anyway and got it started and i asked my daughter "did the brake lights come on?" she said no...so i walk back there and sure enough they did not come on because they were already on.... permanently..so i thought great they are working and i just have to adjust the switch to work. well i adjusted the switch and now the brake lights will not come back on.

so i am figuring that it is somewhere close to the switch area....but wiggling wires and stuff i can't duplicate it and narrow it down. trying to get my 4 and 7 year old helpers to yell if the lights turn on is more difficult than figuring out the wire diagrams!

[Longhorn 70]

is the blinker light on??
yes
No
yes
No
...............