Hi, all;

I have a 2020 STX Screw 4x4 2.7 Eco into which I just installed a set of Alla LEDs for the low and high beams. Easy installation, and on a road test this evening, I was pleased with the difference in from the halogens. They do need to be aimed downward a bit, even though I checked the aim with the halogens prior.

However, I noticed one issue that I wanted to ask the forum about. This truck has the Auto Power Engine Down feature. This feature is activated by default when the engine powers on, and to disable it, you have to use a button on the dash.

I noticed that when I stopped at a light and the Auto Power Down activated, the headlamps noticeably flickered for a second when I released the brake and the engine powered to full. There was no other evidence of this as I drove, applied the brakes when slowing or at any other time. I thought about why this was happening, and decided to deactivate the Auto Power Down to see if there was a difference. Sure enough, when I stopped with it off, no flicker.

I wondered if this is a known issue and if there's a fix for it. I should not that I did not swap the fog lights, in case that matters.

I appreciate any advice or insight on this.

 

I think the factory LED lights have a capacitor or something in their ‘ballast’. I have a set of JW Speaker auxiliary lights that have their relays activated by the factory headlight wiring harness on my 2017. The factory LED headlights don’t flicker when the auto stop restarts...the JW Speaker LEDs do. The JW Speaker lights get main power from the battery.

So, now we know the flicker is from the factory headlight harness. The only thing I can think of is using a capacitor to power the circuit for those milliseconds that the power drops out during restart. Or, integrate a slower relay that won’t drop out for those few milliseconds

 

Good information. I'm wondering if there's a way to add such a capacitor in-line with the new LEDs that would help fix this issue. I'll have to look into this.

Thanks.

 

Most (if not all) LED assemblies usually have a constant-current circuit because the LEDs are sensitive to the amount of current flowing through them. I suspect (but I I don't know for sure), that when the auto-start-stop activates into the power-down mode, the headlight circuit might power down to DRL mode. This means that the headlights will get a lower voltage to save power. If that's the case, the current limiter will operate in such a way so as to cause some flicker in LED lights.

I know for sure the the LEDs in my truck do not flicker when in full power (as in at night), but I have noticed that during the day, when the lights are in DRL mode, you can see some flicker going on.

 

Your referring to the auto start stop. The factory lights do it also. The lights dim during engine restart. Simple solution is disable the terrible auto stop start.

 

I was advised in another forum to look into disabling the start-stop system, as ford390gashog recommended. I found at least two companies that manufacture devices to do this without modifying the feature in anyway (e.g., changing Forscan codes, jumping wires, etc).

The option I chose is a direct plug-in device that is inserted to the OBDII port and saves the setting of the Start-Stop switch between trips. As you all know, it is always set ON until you physically power it off with the button, and it's reset to ON after the car is shut down and restarted. This module saves your setting while allowing you to continue to use the feature if you want to while driving.

The same companies also manufacture a small harness that can be added inline to the button itself that performs the same function.

The choice is based on whether or not you mind leaving something in the OBD port (which isn't an issue for me; you can remove this one and just replace it when done, or add an OBD splitter cable and tuck it away in the pedal well) or of you don't have an issue popping bezels off the dash to add the harness. I don't mind doing the latter, but it's a brand new vehicle, so the OBD module option is better for me right now.

Just ordered it and will get it in a few days. We will see how it works.

I appreciate everyone's insight and advice.

 

I received the OBD port module for the Auto-Stop-Start on Saturday. and it worked as advertised.

Problem solved.

 

Which brand/model disabling unit did you buy? You seem pleased with it so far.

 

From 4D Tech.
https://www.4dtech.com/startstop