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Accidentally "fixed" my slow windows

7.6K views 28 replies 13 participants last post by  v86sp  
#1 ·
Recently I disabled the "smart" charging system on the alternator by disconnecting the ground wire sensor harness. Truck now has steady 14.4-14.8v even at idle.

With the weather here being so damned cold lately I've had no reason to open any of my windows since. Then we had a warm day. I put my windows down, drove around and enjoyed the fresh air.

When I got back home I noticed the difference. While putting my windows up (which I'm in the habit of doing one at a time to speed them up) to my surprise they went up at a normal speed! I've tried them quite a few times since then. Wanted to make sure it was real and not perceived.

Image


Somebody needs to try this and let me know that I'm not crazy 😂
 
#2 ·
I've had that thing unplugged for a few months and I swear my windows are still slow but I'll have to check again to confirm now that you say it. My right rear seems to be much slower than the rest so it might have something going on locally. I don't remember my last truck being this bad.
 
#22 ·
I spray some silicone spray into the window track maybe twice a year and they go up at a decent/faster speed versus without the spray.
I do the same, every couple of years; genuine aerosol silicone lube, not "WD-40" type.
 
#7 ·
Recently I disabled the "smart" charging system on the alternator by disconnecting the ground wire sensor harness. Truck now has steady 14.4-14.8v even at idle.

With the weather here being so damned cold lately I've had no reason to open any of my windows since. Then we had a warm day. I put my windows down, drove around and enjoyed the fresh air.

When I got back home I noticed the difference. While putting my windows up (which I'm in the habit of doing one at a time to speed them up) to my surprise they went up at a normal speed! I've tried them quite a few times since then. Wanted to make sure it was real and not perceived.

View attachment 346276

Somebody needs to try this and let me know that I'm not crazy 😂
Just to verify- that connector is behind the battery - and all that circuit does is cut the alternator output to help gas mileage?
 
#8 ·
I'm not iffin but that is correct. Per the FSM, the only purpose of the smart charging system they mention is for reduced fuel consumption. Personally unplugged that connector myself sometime back right before Christmas. I have perceived no negatives from doing so and I feel a lot more confident my AGM battery will hold up over time better now.

Every time I've tested the voltage while running, it's at either about 14.4V at startup and 14V a bit later.
 
#21 ·
Running a voltage of 14.4-14.8 will overcharge the battery and shorten its service life. Just sayin...
This is incorrect.
Automotive batteries have been charging at full voltage before the advent of the VVCS, with no overcharging or shorter life spans.
IN FACT... today's VVCS systems actually have a tendency to shorten the life expectancy of the batteries by NOT providing ENOUGH voltage for sufficient charging. Hence the reason for the VVCS disconnect. Also, most alternators have 'limiters/regulators' to avoid overcharging.
Just sayin... ;)

The Car Voltage Regulator (How It Works + How To Test It)
 
#23 ·
This is incorrect.
I'll respectfully agree to disagree. Lead acid batteries are typically 2.2v per cell. 2.2x6 cells= 13.2v. 13.8 volts is a typical charge voltage to prevent battery overcharge (which damages the cell plates over time).

The listed article lists a top voltage of 14.5 (too high) but folks in this thread are seeing voltages of up to 14.8 with the VVCS disconnected.

A quote from the linked article:
2. Can A Bad Voltage Regulator Ruin A Battery?
Yes, a bad voltage regulator can definitely ruin your car battery.
If too much voltage is flowing to the battery, it can warp the platers and destroy your battery.

IN FACT... today's VVCS systems actually have a tendency to shorten the life expectancy of the batteries by NOT providing ENOUGH voltage for sufficient charging.
My 2017 SV is on its original battery. Just sayin...
 
#26 ·
All I know is that my VVCS was un-modded/intact and my expensive Odyssey AGM only returned 23 months of service before kicking the bucket. I'll never know if charging at a higher voltage could have extended the AGM's life or not.
My Group 24 flooded/wet cell battery replacement (800cca) has exceeded 4 years of service - and still going STRONG.
 
#27 ·
I'll have to check to see which battery I have but I got my 2012 in 2019 and has the same battery.. still going strong! Never use to do it on any vehicle but with my 08 pathfinder I started pulling the keys out of the ignition every night, (Garaged) I thought I might have been having charging issues. After the battery went all of a sudden and put a new battery in and a few months later it died, I checked everything I knew to check and all was good. I think I just got a dud, anyways I've made it a habit to pull the key from ignition every time I park it for the night. Same with my truck dunno if it matters but it doesn't hurt. No problems since on either and they do sit sometimes days at a time or longer.

As for the windows.. I put rain guards on and the silicon really helped!