#1  
Old 06-27-2020, 07:06 PM
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dpoltzer dpoltzer is offline
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Default 1970 T/A lights on all the time?

Home stretch on the restoration and I have an electrical issue. Issue is that the external lights come on as soon as I install the battery cable on the battery post even though the headlight switch is in the "off" position. The headlight switch is new (Auto Zone #SW-144). I then replaced the HL switch with another new one and the same condition exists. I then installed a different High Beam switch I had laying around (Used) but that had no effect. One odd thing is that the HL switch has 3 detent positions rather than the typical 2. (parking lights and then Head lights). Does anyone know if this is the wrong switch or should I look in another direction? Thanks

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Old 06-28-2020, 04:49 AM
Geoff Geoff is offline
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If you have a headlight relay, I would check that.

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Old 06-28-2020, 08:22 AM
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Need to find out where power is coming from.

I'd start by un-plugging the dimmer switch and probing the terminals with a test light. If green or tan shows to have power... It'll give us a direction to be looking. Blue wire should turn off and on with the headlight switch.

Clay

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Old 06-28-2020, 08:33 PM
Goatracer1 Goatracer1 is offline
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Are you sure it's Auto Zone? There is no listing for SW-144. They list S427, S415, S427P and 55128. They have either 6,7 or 8 terminals. Do the lights go off if you unplug the switch? If they go off check to see that there is battery voltage to the correct terminal. If voltage is correct check continuity thru the switch. There should be infinite resistance with the switch off.

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Old 06-29-2020, 08:22 AM
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it is an SW144 on the Auto zone site and it has 7 terminals/blades. My H.L. plug has 6 "live" terminals but does accommodate 7 blades. I will test dimmer switch wires later today.
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Old 06-29-2020, 11:40 PM
Goatracer1 Goatracer1 is offline
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It will NOT be the dimmer switch. The dimmer switch gets it's voltage from the head light switch and sends it either to low or high beams. With the head light switch disconnected there should be NO voltage to the dimmer switch.

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Old 06-30-2020, 02:16 PM
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May or may not be related: volt gauge, oil pressure gauge and tach do not work as well. Could this be the printed circuit board and could all of these demons be related?

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Old 07-02-2020, 01:09 PM
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Default Update.

I disconnected the H.L. switch and when I connect up the battery, the marker lights and running lights are still on. Ideas?

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  #9  
Old 07-02-2020, 03:59 PM
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Default update again.

I disconnected the turn signal switch and that now kills the parking lights etc. I will replace the T.S. switch and see if that cures the problem.

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Old 07-02-2020, 07:59 PM
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Any chance the ground wire for the front lights has got hooked to a power source of some kind? Then unplugging switches breaks the ground path of power coming from the wrong direction.

Before you do any more part swapping.... Do some testing on front light sockets to see if there is power there that doesn't belong.

Make sure something didn't get crossed up with headlight ground and horn wire or something along that line of thinking.

Clay

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Old 07-03-2020, 02:14 AM
Goatracer1 Goatracer1 is offline
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You might want to check the wiring harness bulkhead connector. I have seen lots of problems in the connection there.

  #12  
Old 07-04-2020, 09:58 PM
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Default Update.

Replaced the turn signal switch and now the Headlights and parking lights work correctly. Remaining problems are as follows: Turn signals do not blink at all even though I replaced the flasher unit. Also, Brake lights stay on all the time. I also noticed that the tail light housing (The plastic housing that the bulbs twist in to) was very, very hot to the touch. The bulbs are new and bright but I do not believe the housing should get this hot. Ideas? thanks again.

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Old 07-05-2020, 08:07 AM
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Have you got the stop-light switch adjusted so the brake lights can cut off?

Brake lights do generate a bunch of heat. Under normal conditions they don't stay on for any great length of time.

What did you do to fix the headlight and parking light problem? Hot wires for them don't go through the turnsignal switch.

The flasher you changed under the dash or in the fuse box?

Clay

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Old 07-05-2020, 08:50 PM
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Replacing the Turn Signal switch corrected the Head light issue. The double brown wires that feed the headlight switch were hot all of the time even with H.L. switch in off position. This was causing the H.L. issue. Concerning the turn signals; I replaced the round canister that mounts to the E-brake assembly with a new one that I bench tested and works. The small squarish switch that has two spades and plugs in to the fuse block has not been replaced. Are they available and what is their purpose (4-ways?) When I have a chance I will work on adjusting the parking brake switch which could very well cure the brake lights always on issue. Thanks much.

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Old 07-06-2020, 12:42 AM
Goatracer1 Goatracer1 is offline
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When you say you replaced the cannister on the E-brake do you mean the brake PEDAL? If you unplug the switch at the brake pedal the brake lights should go OUT. If they do then you either have not adjusted the switch correctly or the switch is bad.

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