Surging with blinker on

[johnsonnate]

Alright, so I installed LEDs everywhere on my exterior, all blinkers, reverse and brake lights and corner markers. Now, I just managed to install the LED flasher but the runner jumps in RPM whenever my blinker is on, as soon as it turns off the engine drops back down to a normal RPM.

In addition to this, I noticed today on the highway, that when I have my foot on the gas, aka not on cruise, and I put my blinker on the truck "surges" and it's kind of a rhythmic surging.

Now, I have no idea what could possibly be causing this. My only thought is that I currently think I have a vacuum issue, so maybe there is a short somewhere that is exacerbating this vacuum issue?

 

[alumarine]

Almost sounds that it's putting a load on the alternator at idle.
The revs drop as the alternator tries to up the amps.

 

[TheDurk]

What happens with Hazard lights? What happens if you put your old Flash relay back in? What happens with new relay but you go back to bulbs?

 

[J4R]

It's probably the LEDs.. Same thing happened to me on two previous 4runners. The Overdrive kicks in and out at the pace of blinker/ Cruse control will disengage when blinker is hit. Noticed it after changing the brake lights years back. Swap the brake lights back to halogen and possibly turn signals and see if it goes away. Hope that helps.

 

[johnsonnate]

What happens with Hazard lights? What happens if you put your old Flash relay back in? What happens with new relay but you go back to bulbs?

Hazards don't mess with the RPMs, old flasher in causes it to hyperblink and surge, and I'm pretty sure that it doesn't happen with the old bulbs. I'm assuming it's because of the LEDs

It's probably the LEDs.. Same thing happened to me on two previous 4runners. The Overdrive kicks in and out at the pace of blinker/ Cruse control will disengage when blinker is hit. Noticed it after changing the brake lights years back. Swap the brake lights back to halogen and possibly turn signals and see if it goes away. Hope that helps.

If it is the overdrive kicking in, is there anything that can be done aside from swapping in the old halogens?

 

[RAD4Runner]

Do as TheDurk says ^^ and see.


Could be this, too:

Almost sounds that it's putting a load on the alternator at idle. The revs drop as the alternator tries to up the amps.

It's probably the LEDs..

Perhaps the LED's have the load resistors built-in and those draw more current than the standard halogens, and drop your voltage to much. LED light load resistors are a dumb idea. They negate the energy-saving benefits of LED's.

OR bad connections so more voltage is dropped across the resistance of connections. Good electrical connections should have bare, shiny metal contacting bare, shiny metal.

 

[TheDurk]

Hazards don't mess with the RPMs, old flasher in causes it to hyperblink and surge, and I'm pretty sure that it doesn't happen with the old bulbs. I'm assuming it's because of the LEDs



If it is the overdrive kicking in, is there anything that can be done aside from swapping in the old halogens?

I'm assuming you are counting on your new flash relay to avoid hyperflash and there are no resistors in the circuit. I can't see any cross-connection between the turn signal circuit and the Transmission/Cruise circuit, just the stop lights. If it is confirmed that the old incandescents (they aren't halogens) resolve the problem, I would suspect that if you added resistors that are used to solve hyperflashing to the turn circuit, you would probably fix this problem, too. Don't ask me to prove it by logic, 'cuz there ain't any, but my gut says it would work.

Try driving with O/D OFF engaged, and see if the problem stays away. That would confirm that @J4R is on to something--I'm just not sure what, why, or how.

 

[TheDurk]

Do as TheDurk says ^^ and see.


Could be this, too:



Perhaps the LED's have the load resistors built-in and those draw more current than the standard halogens, and drop your voltage to much. LED light load resistors are a dumb idea. They negate the energy-saving benefits of LED's.

OR bad connections so more voltage is dropped across the resistance of connections. Good electrical connections should have bare, shiny metal contacting bare, shiny metal.

Really? How much energy do you think is saved by turn signals going LED? If a turn signal bulb is on for 20 seconds every mile (probably high), in 100k miles that is 2E6 seconds or 555 hours. At about 25w, that's 13kwh in 100k miles. With a typical engine efficiency of 40%, a belt efficiency of 98% and an alternator efficiency of 55%, this leads to an overall energy conversion efficiency of about 21%. Assuming a fuel cost of $4.00/gal, (just a guess looking forward) this leads to an on-board electrical power cost of $0.51/kWh, or all of about $6.50 or a little over a gallon and a half in 100k if the cost is reduced to zero with the LEDs.

Not a big deal. It is a little more relevant when you put resistors on all the full-time use or night time use bulbs because of CANBUS problems, but we don't have that issue. Just turns is trivial.

I don't think the load resistors are built in, because he reported hyperflashing with the old relay (one of the reasons I asked the question). So the LEDs couldn't be drawing MORE current than the incandescents.

 

[RAD4Runner]

But load resistors are still enough to cause voltage drops even IF momentary, which are not ideal. Plain LED bulbs AND electronic flasher like O.P. used are still the way to go....

I don't think the load resistors are built in, because he reported hyperflashing with the old relay (one of the reasons I asked the question). So the LEDs couldn't be drawing MORE current than the incandescents.

Then, this ^^^

 

[johnsonnate]

So I went out this morning to run some errands, and I tested the overdrive question, it's not kicking on, I turned it off and the RPMs jumped even higher when on the gas than just having the blinkers on. I want to get back out and test the old bulbs again but it's really cold and I just don't want to go back outside...:shrug:

 

[benhameen]

Hello, I'm trying to re-up this thread as I'm having the same issue. When I turn on the blinkers, I get a surge in RPM of about 250 RPMs, and then it goes back down as I turn off the blinker. But the blinker works just fine, timing wise.

But then my blinker will start hyperflashing, then the RPMs will not surge.

It hyperflashes so fast that the indicator on the dash doesn't even light up.

Can anyone help out with this?

 

[brillo_76]

Happen to have led in first your turn signals. I read somewhere that the led will not let current through and messes with the cruise control.

Sent from my SM-J337V using Tapatalk

 

[phattyduck]

A few systems in the vehicle (transmission control, cruise control, high beam indicator, ABS system, etc.) require the filament of an incandescent bulb (or appropriate load resistor) to be in place to work properly.

Since you changed everything to LEDs, these are the issues you will see. It is unlikely anything is actually wrong with your truck.

-Charlie

 

[benhameen]

Wouldn't the LED relay (which I have) prevent this issue?

 

[phattyduck]

Wouldn't the LED relay (which I have) prevent this issue?

That only fixes the speed of the blinkers...

There is a small chance you still have an issue with your gauge cluster flex circuit board - but to diagnose, you'll need to swap back to incandescent bulbs first.

-Charlie

 

[benhameen]

So new development. I have noticed that the ABS light will come on and my turn signal will flash at the correct speed. But when the turn signal is working normally the RPMs will go up 500 RPMs while the turn signal is being used, and will go back to normal RPM when the turn signal is turned off. Then the ABS light will come back on again sometimes after a day, sometimes after a couple of weeks, and the turn signal will blink so fast that the internal light never actually comes on, and the RPMs no longer rev up when using the blinker.

Any insight would be much appreciated.

 

[phattyduck]

Have you swapped all your bulbs back to incandescent to check to see if that is the problem?

-Charlie

 

[turbodudey2]

If you have a trailer light converter box installed, that could be the source of interference.

I installed a LED 3rd brake light bulb a while back (had LED tails already as well) and observed the same torque converter lock/unlock in sync with the turn signals and could visually see voltage backfeeding into the stop lamp circuit from the turn signals. The brake lights would very faintly flash in sync with the turn signals which then triggered the torque converter to lock/unlock.

With no other apparent connection between the turn signal circuit and the stop lamp circuit, a faulty trailer light converter box may be the source of the spurious voltage.

I swapped my 3rd brake light bulb back to incandescent to resolve the issue. I have also since replaced the trailer light converter, but haven't gone back to test a LED bulb again.

 

[benhameen]

I changed the rear turn signals but not the front as they are hardwired SRQ turn signals. But when I switched the rear, it actually got worse. When the turn signal on, it flashed so rapidly that it sounded like a large bug that got stuck in a bug zapper.

But I never got to switching the 3rd brake light. I'll see what that does.

 

[phattyduck]

I changed the rear turn signals but not the front as they are hardwired SRQ turn signals. But when I switched the rear, it actually got worse. When the turn signal on, it flashed so rapidly that it sounded like a large bug that got stuck in a bug zapper.

But I never got to switching the 3rd brake light. I'll see what that does.

The issue would be more of a problem with LED tail/brake lights than turn signals... (I have LED front signals too, hasn't caused a problem other than needing an LED flasher)

-Charlie