Turn signal/Headlights issue.

porter18 · August 20, 2017

2005 Silverado Crew Cab

The other day I noticed my right turn signal was lit dimly on the dash but it turned off within a few miles of driving.

Then it happened again on Friday morning lasting for around 20 minuets of driving through the middle of nowhere so I didn't want to stop. This time the dash actually chimed and said "turn signal on" until it stopped.

Finally on Friday night it did it again when I left the store, This time I was able to get out and test exactly what was happening.

First noticed that the parking filament is off on the front turn signal and the turn filament was barely lit, at the same time the low beam on that side is visibly dim and both high beams are glowing just a bit.

The driver turn signal works fine, but when I turn on the passenger side one it flashes properly in the dash, but all the lights that are acting strange on the truck just pulse a bit with the flasher.

The issue is intermittent and only occurs when headlights are on. Switching to parking lights only stops the issue.

Pulled some bulbs to look for possible corrosion or weak connections and had some interesting results.

Pulling the front or rear turn signal bulbs had no effect on the issue

I cant remember which did what at the moment but did test unplugging the high and low beam bulbs on that side and one caused the issue to correct, and pulling the other caused the parking and turn bulbs to go out completely.

Couldn't find any other similar issues online anywhere so I'm hoping for a little bit of guidance before I tear the whole front corner apart to examine the entire harness.

Since the first suggestion was a ground issue, I forgot to mention I pulled both front body grounds for the lights last month and cleaned them up because the horn was randomly squawking when togging brights. ~~So I wouldn't think that particular ground point would be weak again. Unless maybe I need to cut the whole connector off and re attach the 5-6 wires to a new connector to bolt to the body?~~

Multi tester revealed that the connection between those wires and that frame are good, but the connection between that frame rail and the rest of the truck is weak.

Question now becomes is there a ground strap for that part of the frame or is it just bad connection through frame bolts? Or do I need to add a ground strap of my own somewhere to improve the connection?

Justin101714 · August 20, 2017

Sounds like a ground problem to me. Check the ground on the drivers side under the truck, it's mounted to the frame, just rearward of the left front wheel well plastic

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porter18 · August 20, 2017

Sounds like a ground problem to me. Check the ground on the drivers side under the truck, it's mounted to the frame, just rearward of the left front wheel well plastic

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I assume your talking about the main ground for the battery? If so, I wouldn't expect that to cause localized issues for only a couple circuits.

Though I will probably double check it tonight to see if it appears bad.

Justin101714 · August 20, 2017

I assume your talking about the main ground for the battery? If so, I wouldn't expect that to cause localized issues for only a couple circuits.

Though I will probably double check it tonight to see if it appears bad.

This should be a grind for multiple things. The main battery ground is on the engine block and goes to the front portion of the right side of the frame

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porter18 · August 20, 2017

This should be a grind for multiple things. The main battery ground is on the engine block and goes to the front portion of the right side of the frame

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Got the multi tester out and that ground connection on the frame below the driver door is good, however, the connection between that lower frame across the front of the truck where all the headlights/horns grounds bolt on, has high resistance to the rest of the test points I tried, including the battery cable.

Justin101714 · August 20, 2017

Looks like you found it then [emoji1417]

Also don't forget a multimeter on a ground isn't a good test. The small amount of signal sent from the meter through the ground just doesn't really test the ground efficiently. The best way is to light a halogen bulb through the ground and voltage drop test across the load. Should be within 0.2v of your source voltage.

If you had some strands broken within the ground wire. The meter wouldn't pick that up. But putting a load on the circuit will.

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porter18 · August 20, 2017

Looks like you found it then [emoji1417]

Also don't forget a multimeter on a ground isn't a good test. The small amount of signal sent from the meter through the ground just doesn't really test the ground efficiently. The best way is to light a halogen bulb through the ground and voltage drop test across the load. Should be within 0.2v of your source voltage.

If you had some strands broken within the ground wire. The meter wouldn't pick that up. But putting a load on the circuit will.

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For the average person a multi meter wouldn't be a good test. But I do have some electrical experience/education and was reading the Ohm resistance numbers on each point, most points around the truck have less then 5 ohms resistance. while the front cross brace was showing in the 150-200 ohms resistance.

That being said I did finally find the issue after pulling all the light assembly's so I could reach behind them while still hooked to all the bulbs and did a "wiggle test" of all the wires.

Driver side ground only has two wires and about 3 inches past where they enter the corrugated wire loom I found these.

One of the wires is loose in the crimp connection, add that to the fact the shrink tube was too big for the wires so water could get into the connections.

Soldered in a new section of wire with some liquid electrical tape and new correct sized shrink tube over that, and so far the issue seems to be fixed.