Labor Day Putting down your wrenches or time for MORE wrenching? 
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Dec 2013 Posts: 224 'Bolter | | 'Bolter Joined: Dec 2013 Posts: 224 | A follow up on my headlight/dimmer switch issues. Again it’s a ‘47 AD 3100. Was having issues with hi/low beams and the dimmer switch. Suggestions I got here were spot on. I now have hi/low beams that respond correctly with the dimmer switch, which is new. Progress is great.....and a big thank you for the help.
Thought I had solved the problem but I realized it still is kicking me.
Everything works fine, wiring seems to make sense. Grounds are good. I will be improving the grounds though on the inner fender ground with a new ground to the frame.
The issue now is the dash hi/low light stays lit no matter if the headlights are hi or lo. Obviously I did something wrong....but lights all work. Before this mess, the indicator light worked perfectly. The only thing I can think of is the lead from the light switch to the dimmer switch is connected poorly. The PO re-wired for the lights, I changed the dimmer switch. So I may have “fixed” something, creating more headache.
Anybody have an idea 💡 where I went wrong? Or better yet, what the heck I can try to fix the dash light. ( I have thought about a piece of masking tape over the light!!). Lol | | | | | Joined: Feb 2004 Posts: 29,740 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,740 | It sounds like the wire that powers the dash light is connected to the wrong terminal om the dimmer switch. If it's connected to the wire from the headlight switch to the dimmer, the light will stay on all the time, no matter which beam is selected. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
| | | | | Joined: Aug 2005 Posts: 6,377 Ex Hall Monitor | | Ex Hall Monitor Joined: Aug 2005 Posts: 6,377 |
Save a life, adopt a senior shelter pet. The three main causes of blindness: Cataracts, Politics, Religion. Name your dog Naked so you can walk Naked in the park.
| | | | | Joined: Aug 2001 Posts: 1,299 'Bolter | | 'Bolter Joined: Aug 2001 Posts: 1,299 | Any chance you have a dash light that goes on and off with the dimmer? Could it be as simple as having the wrong light in the wrong hole? | | | | | Joined: Dec 2013 Posts: 224 'Bolter | | 'Bolter Joined: Dec 2013 Posts: 224 | Traced all wires. Checked all bulbs and functions. Everything checks out with a meter. The rheostat in the original light switch barely works. I’m going to order another original style switch as I think this appears to be a logical the answer. Thanks again for the pointers. | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | "The rheostat in the original light switch barely works."
rheostat (and sometimes other electrical contact items): did you use/try a non-silicone/non-oil electrical contact cleaner? | | | | | Joined: Feb 2004 Posts: 29,740 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,740 | "What we have here is a failure to communicate"! The dash light dimmer rheostat has NOTHING to do with the high beam indicator- - - -that light is either on or off, no dimming involved. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
| | | | | Joined: Feb 2019 Posts: 4,471 AD Addict & Tinkerer | | AD Addict & Tinkerer Joined: Feb 2019 Posts: 4,471 | Are you sure you have the headlights wired correctly? If you switched the ground and the high beam wires at the terminal, the headlights would still work (may be a bit dim) and could cause the condition you are seeing. If this was the case, when you switched to the low beams, the lights would still work and mixed up ground would back feed the high beam indicator to make it light, thus would be on all the time the headlights were on.
Last edited by Phak1; 02/11/2021 1:09 AM.
Phil Moderator, The Engine Shop, Interiors and Project Journals1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc BrakesProject JournalsStovebolt Gallery Forum | | | | | Joined: May 2015 Posts: 10,997 Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums | | Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums Joined: May 2015 Posts: 10,997 | Actually that wire to the high beam indicator comes from the fuse box. Here's the Wiring Diagram.
Last edited by klhansen; 02/11/2021 4:34 AM.
Kevin 1951 Chevy 3100 work truckFollow this saga in Project JournalPhotos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together. | | | | | Joined: Dec 2013 Posts: 224 'Bolter | | 'Bolter Joined: Dec 2013 Posts: 224 | Geez. Looked at the wiring diagram but never noticed the ground from the hi beam fuse. Appears my logic wasn’t too logical! I will follow up today with your suggestions. We are in the midst of a cold snap here.......takes a bit for my shop to warm up! | | | | | Joined: Feb 2019 Posts: 4,471 AD Addict & Tinkerer | | AD Addict & Tinkerer Joined: Feb 2019 Posts: 4,471 | I had the same situation happen to me last year, when I replaced the old wiring going from the terminal located on the fender to the headlight socket. I had wired the drivers side incorrectly and the high beam indicator never went off as long as the headlights were on. My ‘52 high beam indicator is wired to the H/L switch and the only real difference between a ‘52 and the ‘47 in the headlight wiring, is the added fuses on the ‘47. The high beam indicator light is still being fed from the power to the high beam (whether its fed from the H/L switch or the fuse panel). If the ground and the high beam wiring from the headlight bucket is switched at the terminal block on the fender it can back feed the high beam circuit with the low beams on. The point I’m trying to make is the wiring needs to be rechecked against the circuit diagram that klhansen provided.
Phil Moderator, The Engine Shop, Interiors and Project Journals1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc BrakesProject JournalsStovebolt Gallery Forum | | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | The bottom line, the high beam light wire needs to be hooked to the leg of the dimmer switch that goes to the high beams, whether or not it stops somewhere else.
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires. '47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle. '54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed. '55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: Dec 2018 Posts: 2,450 'Bolter | | 'Bolter Joined: Dec 2018 Posts: 2,450 | tclederman Tuner cleaner is what your thinking of. Great stuff,will clean dirty contacts then just dry-up and leave. Had a guide 7 wire turn signal switch I thought was dead soaked it working fine today !! | | | | | Joined: Dec 2013 Posts: 224 'Bolter | | 'Bolter Joined: Dec 2013 Posts: 224 | Final Update:
All these suggestions were very helpful. This was a long and tedious project. Traced all wiring via wiring schematic from dimmer, switch to fender terminals and grounds. Multimeter was used to find my “leak”. Phak1’s experience pretty much mirrored mine. Ultimately, I had the ground wires and lo beam wires switched at the terminal blocks. Once I reversed the wires on each side, the clouds disappeared and the sun came out! I think the Red Sea parted again! Needless to say I was happy and grateful for all the help everyone offered. Thanks!, | | | | | Joined: Feb 2019 Posts: 4,471 AD Addict & Tinkerer | | AD Addict & Tinkerer Joined: Feb 2019 Posts: 4,471 | I’m glad you got it all worked out! Isn’t this forum great!
Phil Moderator, The Engine Shop, Interiors and Project Journals1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc BrakesProject JournalsStovebolt Gallery Forum | | |
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