Turn signal/AC connection?

The_Red_Baron

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Howdy all,

A few nights ago, i took the red bomb for a ride, and noticed something strange......

This year happens to be the first year I've had AC and led turn signal conversion in the winter. Normally, the turn signal and AC work fine (in the summer months).

Recently, I've had to drive with "defrost" mode on, because I left my ice scraper at home like an idiot, and need to have climate control when I'm driving.

To make a long story short, whenever defrost is on, a few things happen:

1. AC compressor cycles on and off fast, not like normal cycling, and it's not intermittent. It continuously fast cycles with no real pattern.

2. When using the turn signals, the indicator seems to flash in sync with the cycling of the compressor.

3. It doesn't show in the video, but my rear window defrost indicator also flashes in sync with the compressor. When it's on, however, it does not flash.

Anybody know why this happens? If I run anything else in the temp control board, it's perfectly fine (as far as I remember). I didn't have this problem in the summer, so I'm just wondering if the AC circuit and my turn signal circuit are crossing somehow? I'm at a loss, but in the mean time I can just run straight heat untill I can figure it out. I'll try to upload the video in a comment later I guess.
 

volare 77

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My guess, which is just a guess is the clutch on the compressor is going bad.
 

80mirada

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is your A/C new? any new parts in it? the cycle switch may be bad or not have good contact inside its tube. you could have a loose/bad contact in a body ground.
 

Aspen500

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The clutch can still engage at low temps provided the refrigerant pressure is high enough. I've had the compressor on my '96 Dakota cycle with the defrosters as cold as 20 degrees. Eventually, the refrigerant pressure gets low enough when it's cold that the compressor won't cycle anymore.

That said, I'm not sure about what you describe. Maybe unplug the compressor clutch or low pressure cycling switch and see if the other problems go away.

I can't view your video since "You need permission" it says and guess I don't have permission, lol.
 

The_Red_Baron

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is your A/C new? any new parts in it? the cycle switch may be bad or not have good contact inside its tube. you could have a loose/bad contact in a body ground.
From what I remember, I had my AC system fixed 2 summers ago. The only things not replaced were the condenser, compressor, and lines. All the other components were replaced.

That being said, I've noticed a small leak front the front of the compressor, so I'm planning on replacing the compressor eventually.
 

The_Red_Baron

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The clutch can still engage at low temps provided the refrigerant pressure is high enough. I've had the compressor on my '96 Dakota cycle with the defrosters as cold as 20 degrees. Eventually, the refrigerant pressure gets low enough when it's cold that the compressor won't cycle anymore.

That said, I'm not sure about what you describe. Maybe unplug the compressor clutch or low pressure cycling switch and see if the other problems go away.

I can't view your video since "You need permission" it says and guess I don't have permission, lol.
Yeah, sorry about that. Couldn't easily post the video, even after trimming, so I just posted the drive Link.
 

BudW

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Some years have a diode for when the A/C clutch disengages, that it keeps a back signal going down the power wire. If you have a diode, it will be close to the a/c clutch wiring pigtail – and it can go bad.
If yours does not have a diode, you might be able to add one. It sounds like that might be an issue – maybe.

Another thing you can do is when you push in the DEFROST button on A/C control head, is to pull the button back out. Doing so (even in A/C mode) will disengage the A/C compressor.
I do that often when using the A/C and don’t feel like turning A/C off. Just disengage the compressor for a bit, then push button back in to resume cooling.
BudW
 
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