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blinker trouble??

Twisted Steel Performance

Anything worth doing is worth overdoing.
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About 3 months ago I had a new heavy duty headlight harness made that draws power directly from the battery's, it's been working great sense then.... up until this morning that is....

Light switch on, head lights work as they should, right turn signal dash light stays lit, right turn won't flash at all, left will work just fine....

Head light"s off, both turn signals blink fast AND dash lights sort of blink dimly....

I figure this is a ground issue or maybe the flasher unit... the new harness is grounded in 2 places, 1 on p/s battery, 1 on the d/s body @ the battery area...

Where should I continue checking... headlight switch, blinker switch, flasher unit, etc???
 
Look at the grounds first.
A bad ground connection will cause the voltage to travel through other filaments to a grounding source.
Weird occurrences such as what You are experiencing most always leads to a bad ground.
 
Don’t know maybe try hazards see if all bulbs blink correctly. If ok I would think it points to turn switch.

Maybe wiggle turn lever or try to manually blink it see what happens.

Doesn’t it fast blink on dash if bulb burnt out?


Had a blonde girlfriend I asked to help work on some turn signals. She stood behind truck I flipped on right turn signal and asked if It was working ... she said yes, wait no, uh yes, no, yes, no
 
With the 4way on all blinks as it should and all bulbs are lit...

I noticed this afternoon that the amp gauge bounces when the turn lever is moved to blink position so me also think the column will be apart soon... I don't quite understand the worst of it shows up when the headlights are on tho... I'm going to recheck all the grounds first and pull the grill off and make sure nothing is pinched as that's less work than the column is....
 
Would think with head lights on the power (voltage/current) required to blink the lights is a tad more since more current is flowing through the grounds. Especially if you have relays feeding the headlights more than stock.

Any difference in hi beam vs low beam headlight with turn signal function?

If 4 ways work fine with head lights on seems to point to turn switch. I could see a weak right contact not wanting to supply enough current such that voltage drops to cause something wierd (a back feed or fighting voltage against the turn signal voltage). This might have a combo problem with right front side ground.

Might try to take out front right blinker bulb to see if rear works correctly. Note dash may blink fast or stay on indicating bulb burnt out. And or take out rear right bulb to see if front works. etc.
 
the new harness is grounded in 2 places, 1 on p/s battery, 1 on the d/s body @ the battery area...

This is a classic "ground loop". Consider how thick the battery cables are for a second and then where the main source of voltage/current is when the engine is running. Starting the engine with a 10HP starter will have current flowing through everything connected to the battery back to the engine block - so small wire becomes crispy as current flows to the body and back to the engine through the big ground cable from body to engine. When the engine is running you have 6+ amps continuously to the battery up to the limit of the alternator ~100A depending on how low the battery is.

Short answer is NEVER ground anything to the battery. Big three only so engine and body can go to the battery, but, you still have an engine to body ground strap. Positive is same issue - never take power off the battery: and for noise reasons not off the alternator lug.

I suggest you have toasted the ground wire due to the ground loop. It gets worse when the battery ground gets some corrosion and current really flows through the ground loop. You only need to ground the harness at a body ground with a good ground strap connected elsewhere to the engine.
 
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