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| | | Forums66 Topics128,052 Posts1,055,719 Members48,426 | | Most Online14,466 Apr 26th, 2026 | | AD Chevy Trucks Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Mar 2009 Posts: 62 Wrench Fetcher | | Wrench Fetcher Joined: Mar 2009 Posts: 62 | just finished the restore of my '56 3600. new wiring, lights and aftermarket turn switch when I press the brakes the left turn indicator,left lamp and right brake light come on. With the brake off the turn lights work properly. I have checked grounds and bulbs I am suspecting a bad diode or crossed wire in the switch, your thoughts? | | | | | Joined: Jul 2001 Posts: 3,887 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Jul 2001 Posts: 3,887 | no diodes involved in anything 1956, most likely wires wrong at the connector where they come out of the column, or much less likely, a defective new switch - see the wiring diagram linked on your other post
Bill | | | | | Joined: Jul 2001 Posts: 3,887 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Jul 2001 Posts: 3,887 | then look in the tech tips, there's a good aftermarket signal article there, still likely a wiring problem, checking if that's all correct will be needed before suspecting a defective new switch .... and still no diodes involved  Bill | | | | | Joined: Oct 2009 Posts: 136 Wrench Fetcher | | Wrench Fetcher Joined: Oct 2009 Posts: 136 | I had a similar problem when rewiring mine, had one wire crossed and took 5 min's to locate w/ diagram in hand. | | | | | Joined: Feb 2008 Posts: 202 Shop Shark | | Shop Shark Joined: Feb 2008 Posts: 202 | If you have dual filament bulbs replace all. A friend of mine had a similar problem and it turned out to be a bad bulb that had the top filament break and weld it self to the bottom filament and cross connect the circuits.
Keep the 216's running. 1949 1/2 ton model #1314 (US 3104) Brian
| | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | I had the exact same thing Hippy is talking about. Look at the bulbs carefully.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn | | | | | Joined: Mar 2009 Posts: 62 Wrench Fetcher | | Wrench Fetcher Joined: Mar 2009 Posts: 62 | I figured it out,kinda, after realizing that the indicators, because of the brake light circuit,flash off of the front turns,I just switched the LF and LR wires, works great! | | | | | Joined: Mar 2009 Posts: 71 Wrench Fetcher | | Wrench Fetcher Joined: Mar 2009 Posts: 71 | I am doing a homemade wiring harness for my custom 53 3100. I have studied the posts on the search feature and the tech tips as well. I found wiring diagrams on later model vehicles but there is still one thing I do not understand. How does the brake light circuit integrate into the turn signal switch without causing the power to feed back to the front turn signals as well? Is there an internal diode in the switch to isolate the front? I understand circuits and basic electronics so there is surely a more clear explanation for this. Since one post said there is no diode in older systems how did they do this? Thanks in advance. | | | | | Joined: Jul 2001 Posts: 3,887 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Jul 2001 Posts: 3,887 | mechanical switching Dan - when no direction selected, the brake power goes straight thru the switch to the rear, when a direction is selected the brake power for that side is routed thru the flasher so that it's interrupted .... of course that means you'll have to wire your lights as the newer ones are done, this 5-9 diagram may help .... study Cletis' tip a bit and it should come clear - there's no connection between the brake and park circuits except when both lights on one side are blinking Bill | | |
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