Headlights and brake lights don't work looking for guidence |
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Headlights and brake lights don't work looking for guidence |
mb911 |
Mar 23 2021, 05:06 PM
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#1
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914 Guru Group: Members Posts: 6,883 Joined: 2-January 09 From: Burlington wi Member No.: 9,892 Region Association: Upper MidWest |
Hi all. The 5 year project is wrapping up. I am working on making it street legal.
Here is what I have 74 chassis harness 914-6 column. Remove the head light relay from the 4cyl. Previous to that the headlights would not turn on anyway. If I jumper the yellow wire on the fuse panel #3 position then the low beam stays on. This is regardless of using the 914-6 column or not. The fogs work, running lights work , turn signals work. Brake lights dont but there were cut wires on the harness down by the switch so that is likely part of the problem. I am also wanting to put relays on each headlight up front like 911s do to prevent any wire fire (IMG:style_emoticons/default/wink.gif) so my question is why the #3 buss wouldn't be energized without jumpering as shown in my picture. My hopes are 2 fold. I am looking for a good high def picture of the brake light switch and wiring on a 74. Then I am looking for the #3 buss(yellow wire low beam) issue. Thoughts? Note in the picture I have the jumper hanging in mid air not attached. Attached thumbnail(s) |
Root_Werks |
Mar 23 2021, 05:09 PM
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#2
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Village Idiot Group: Members Posts: 8,337 Joined: 25-May 04 From: About 5NM from Canada Member No.: 2,105 Region Association: Pacific Northwest |
It almost sounds like you have a short, something is back feeding when you connect bus 3. Oh boy, electrical stuff can take time to track down. Triple check any non-connected wire isn't touching something.
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john77 |
Mar 23 2021, 05:19 PM
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#3
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Senior Member Group: Members Posts: 621 Joined: 21-February 14 From: Los Angeles Member No.: 17,027 Region Association: Southern California |
Not sure if this will be helpful, but if you scroll down on this thread Spoke posted a 74 foglight/headlight wiring diagram.
http://www.914world.com/bbs2/index.php?sho...=342181&hl= There's a lot of good info about the headlight wiring in it. |
mb911 |
Mar 23 2021, 05:26 PM
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#4
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914 Guru Group: Members Posts: 6,883 Joined: 2-January 09 From: Burlington wi Member No.: 9,892 Region Association: Upper MidWest |
It almost sounds like you have a short, something is back feeding when you connect bus 3. Oh boy, electrical stuff can take time to track down. Triple check any non-connected wire isn't touching something. Not sure on a short but seems like the switch is a likely culpret. |
Chris914n6 |
Mar 23 2021, 05:46 PM
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#5
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Jackstands are my life. Group: Members Posts: 3,338 Joined: 14-March 03 From: Las Vegas, NV Member No.: 431 Region Association: Southwest Region |
Headlights only turn on when the car is switched on.
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mb911 |
Mar 23 2021, 05:59 PM
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#6
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914 Guru Group: Members Posts: 6,883 Joined: 2-January 09 From: Burlington wi Member No.: 9,892 Region Association: Upper MidWest |
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framos914 |
Mar 23 2021, 07:44 PM
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#7
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Member Group: Members Posts: 125 Joined: 15-May 14 From: Corona California Member No.: 17,353 Region Association: Southern California |
Do your headlight assy come up but no lights?
You said the fogs are on but no low beam? fog light relay gets power from same place as your low beams (pin 56 on headlight switch) BR/BL wire goes to fog switch then to fog relay to turn on fog lights. From same pin 56 on headlight switch RD/WH wire goes to dimmer relay then YW wire from dimmer relay to fuse F4 and jumpered to fuse F3. Wires from fuses to headlights are good since you said low beams come on when you apply power to #3. The problem has to be wiring from light switch to dimmer relay or dimmer relay to F4. But if your fogs also only come on when you jumper #3 it's the light switch, wiring from ignition to light switch or ignition switch. Make sure you get power on pin 15 of light switch with ignition on. |
mb911 |
Mar 24 2021, 05:08 AM
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#8
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914 Guru Group: Members Posts: 6,883 Joined: 2-January 09 From: Burlington wi Member No.: 9,892 Region Association: Upper MidWest |
Do your headlight assy come up but no lights? You said the fogs are on but no low beam? fog light relay gets power from same place as your low beams (pin 56 on headlight switch) BR/BL wire goes to fog switch then to fog relay to turn on fog lights. From same pin 56 on headlight switch RD/WH wire goes to dimmer relay then YW wire from dimmer relay to fuse F4 and jumpered to fuse F3. Wires from fuses to headlights are good since you said low beams come on when you apply power to #3. The problem has to be wiring from light switch to dimmer relay or dimmer relay to F4. But if your fogs also only come on when you jumper #3 it's the light switch, wiring from ignition to light switch or ignition switch. Make sure you get power on pin 15 of light switch with ignition on. That is very helpful thank you. The fogs come on no issue. The headlights pop up no issue. So now I have to figure out where the dimmer relay is.. that will be today's project when I have a few minutes. |
mb911 |
Mar 24 2021, 01:53 PM
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#9
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914 Guru Group: Members Posts: 6,883 Joined: 2-January 09 From: Burlington wi Member No.: 9,892 Region Association: Upper MidWest |
Anyone know where the dimmer relay is?
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sb914 |
Mar 24 2021, 02:00 PM
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#10
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Surf Guru Group: Members Posts: 4,316 Joined: 25-November 12 From: Brookings,Oregon Member No.: 15,191 Region Association: Southern California |
I think the square one . Not positive although.
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ClayPerrine |
Mar 24 2021, 02:10 PM
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#11
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Life's been good to me so far..... Group: Admin Posts: 15,520 Joined: 11-September 03 From: Hurst, TX. Member No.: 1,143 Region Association: NineFourteenerVille |
The dimmer relay is only used on 4 cylinder cars. If you do a conversion to a six column, you won't have a dimmer relay.
Clay |
mb911 |
Mar 24 2021, 02:13 PM
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#12
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914 Guru Group: Members Posts: 6,883 Joined: 2-January 09 From: Burlington wi Member No.: 9,892 Region Association: Upper MidWest |
The dimmer relay is only used on 4 cylinder cars. If you do a conversion to a six column, you won't have a dimmer relay. Clay Ok thanks then thats what I cut out already per your direction last fall. Just cant figure out why no power at #3 buss and why no headlights. |
ClayPerrine |
Mar 24 2021, 02:17 PM
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#13
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Life's been good to me so far..... Group: Admin Posts: 15,520 Joined: 11-September 03 From: Hurst, TX. Member No.: 1,143 Region Association: NineFourteenerVille |
The power should go to the turn signal switch in the column. then from there it should go to either the low or high beam feeds to the fuse block, depending on the position of the turn signal switch.
Clay |
mb911 |
Mar 25 2021, 07:17 AM
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#14
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914 Guru Group: Members Posts: 6,883 Joined: 2-January 09 From: Burlington wi Member No.: 9,892 Region Association: Upper MidWest |
The power should go to the turn signal switch in the column. then from there it should go to either the low or high beam feeds to the fuse block, depending on the position of the turn signal switch. Clay I am working on determining if there is power to the red and white wire from the chassis to the red on the switch. I would assume if I have that then it should work. If I flash to pass the lights come on. |
mb911 |
Mar 25 2021, 07:27 AM
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#15
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914 Guru Group: Members Posts: 6,883 Joined: 2-January 09 From: Burlington wi Member No.: 9,892 Region Association: Upper MidWest |
And it appears no 12v at the headlight switch red with white tracer and black with blue tracer #56.
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mb911 |
Mar 25 2021, 12:28 PM
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#16
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914 Guru Group: Members Posts: 6,883 Joined: 2-January 09 From: Burlington wi Member No.: 9,892 Region Association: Upper MidWest |
So here is the progress.
I have power to the 914-6 stalk with the headlight switch on and the key on.. however no lights unless I pull back on the stalk. Thoughts? |
framos914 |
Mar 25 2021, 12:39 PM
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#17
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Member Group: Members Posts: 125 Joined: 15-May 14 From: Corona California Member No.: 17,353 Region Association: Southern California |
And it appears no 12v at the headlight switch red with white tracer and black with blue tracer #56. How about pin 15 on light switch with key on. Since you have the 6 column I saw this thread with diagram from Jeff Bowlsby for a 6 cyl. 26, 27 & 28. Are turn signal, ignition switch and light switch. http://www.914world.com/bbs2/index.php?showtopic=298370 |
mb911 |
Mar 25 2021, 01:18 PM
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#18
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914 Guru Group: Members Posts: 6,883 Joined: 2-January 09 From: Burlington wi Member No.: 9,892 Region Association: Upper MidWest |
And it appears no 12v at the headlight switch red with white tracer and black with blue tracer #56. How about pin 15 on light switch with key on. Since you have the 6 column I saw this thread with diagram from Jeff Bowlsby for a 6 cyl. 26, 27 & 28. Are turn signal, ignition switch and light switch. http://www.914world.com/bbs2/index.php?showtopic=298370 I actually have power now and have traced everything back to the turn signal stalk. The problem appears to be the contacts? Not sure yet as both switches I have do this.. very frustrating but I have eliminated the wiring, and switch.. so now it looks to be the turn signal switch. |
Root_Werks |
Mar 25 2021, 02:30 PM
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#19
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Village Idiot Group: Members Posts: 8,337 Joined: 25-May 04 From: About 5NM from Canada Member No.: 2,105 Region Association: Pacific Northwest |
My hazard switch is sort of like that. If you pull it out, nothing unless you push in every so slightly. Just worn out I guess?
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mb911 |
Mar 26 2021, 09:21 AM
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#20
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914 Guru Group: Members Posts: 6,883 Joined: 2-January 09 From: Burlington wi Member No.: 9,892 Region Association: Upper MidWest |
To wrap this up. The diagrams all pointed towards the red wire on the stalk being 12v positive but in reality the white and black should be. This maybe unique to the 2 switches I have but regardless the switch now functions.. now to get brake lights working.
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