MPG Correction Tutorial - AFE Bias Adjustment (via Engineering Test Mode)

[bsenecal]

Maye you should phone home?

Ha ha , yes I am ready to.
Make the real ET would know the magic to get the Maverick into “ET” mode.
Brian

Sponsored

 

[dochawk]

Try offering Reese's Pieces . . .

[odd trivia: the script called for M&Ms, but in one o the great marketing screwups of all time, M&M lawyers threaten to sue them silly if their candy got associated with space weirdos. So they substituted, and made RP as a product!]

 

[bgctcowboy628]

NO. Do NOT press the brake. To get to the ON (but not start) mode you press the start button WITHOUT the brake.

Maybe I should do a video.

I dont have a start button. Any ideas

 

[bgctcowboy628]

Only 2 states. Accessory Mode & Started - using the manual terms. So more of a mixed mode.
Keyed has 3.

Push Button Ignition Switch (If Equipped)

Switching the Ignition Off
When the ignition is on or in accessory mode, press the push button ignition switch once without your foot on the brake pedal.

Switching the Ignition to Accessory Mode
When the ignition is off, press the push button ignition switch once without your foot on the brake pedal.
All electrical circuits and accessories are operational and the warning lamps and indicators illuminate.


Starting a Gasoline Engine


Before starting your vehicle, check the following:

• Make sure that the parking brake is on.
• Make sure that the transmission is in park (P).

1. Fully press the brake pedal.

Note: Do not touch the accelerator pedal.

1. Press the push button ignition switch.

I ain't got one

 

[HeyBales]

I ain't got one

Then turn the key to On when following the process.
The instructions in post 1 say that.

 

[bgctcowboy628]

MPG Correction Tutorial
If your Ford Maverick displays an inaccurate MPG, you can correct it by adjusting the AFE bias in Engineering Test Mode. After calculating my truck's MPG at the pump, I discovered the displayed MPG indicated a value approximately 1.2 MPG higher than the actual value (about 4-5%)

Steps
Follow these steps to enter Engineering Test Mode and fine-tune the AFE bias for a more accurate MPG readout.

1. Enter Engineering Test Mode
   • With the truck off, press and hold the right-side OK button on the steering wheel.
   • While holding the OK button, press and release the Start/Stop button (or turn the key to the "on" position). You do not have to start the engine.
   • Continue holding the OK button for 5-7 seconds until you have entered Engineering Test Mode.
2. Adjust the AFE Bias
   • Use the Up/Down buttons to navigate to the AFE Bias option.
   • If you haven't made adjustments yet, the default value will be 1000 (representing 100%).
   • Use the formula or Siri Shortcut below to adjust your AFE bias so your truck displays a more accurate MPG value.
   • Turn the truck off to exit Engineering Test Mode.
3. Bonus Features
   • Engineering Test Mode also provides access to diagnostic trouble codes, RPM, coolant temperature, and other valuable data.

Calculation Formula
Current AFE Bias value X Calculated MPG / Displayed MPG = New AFE Bias Value

Pro Tip
I recommend repeating this process multiple times over a few fill-ups to calculate a more accurate average. When I did the math, I noticed some variance, so taking multiple readings will help you get a more precise result.

Siri Shortcuts
For iPhone users I’ve included a Siri Shortcuts link below that quickly calculates the new AFE bias value, even if the current bias differs from the default value of 1000. This shortcut makes fine-tuning your MPG quicker and easier on the go.

https://www.icloud.com/shortcuts/679729a810094cee9e26bb64b5142c66

Photos
Main Engineering Test Mode Screen

AFE Bias menu.

I have already adjusted mine from 1000 to 950 (100% to 95% readout)

Diagnostic Trouble Code Menu. There are many more menus as well.

Siri Shortcuts app I built.

Hope this helps!

Thanks

 

[Junglejim]

Great, thanks for sharing this "how to"! Would this be the same parameter to adjust regarding a tire size change? And if your new tires circumference is 5% greater, would you then adjust the AFE upwards 50 points?

 

[mikeymaverick]

Great, thanks for sharing this "how to"! Would this be the same parameter to adjust regarding a tire size change? And if your new tires circumference is 5% greater, would you then adjust the AFE upwards 50 points?

Not necessarily. A larger tire could result in additional drag and actually bring your mile per gallon down. In order to adjust for your tire size, you need to use Forscan. However, Forscan has hard upper and lower limits for the tire sizes it can receive which I believe are closely related to OEM tire sizes.

 

[SUNDOG52]

I'm totally frustrated! Can't get my 2024 hybrid XLT into ET mode using any of the above mentioned methods. Is there a way to adjust the AFE bias using FORScan?

 

[Ferta McDaniels]

Hiya @Sloberdog.

Try this, I finally figured out how to access ET 2 minutes ago on my 2025 Lariat.

I did sit down in my truck and ran through the process to ensure accuracy for my truck.

(Edit-for spacing and ease of reading and format)

1. Already have power "on", in the vehicle

2. Turn power "off (edit-keep your screens on..do NOT turn your screen off!)

3. Press "ok" button

4. Press "brake" with foot

5. Press "power on" button to turn truck on

6. Release "power on" button

7 Release "brake" with foot

8. "ET" letters should appear in 3 or 4 seconds...you may need to hit "OK" to clear seat belt etc screens, but "ET" SHOULD remain once you clear them

9 carry on with setting your "AFE" fuel adjustment etc as you see fit.

Please let us know if this works for you, and good luck,

Andy

This is the only method that would work for me (25 XLT Hybrid). Still want to get in a few more fill ups in before adjusting. Currently I am looking at ~887 for my number

 

[SafetyGuy]

This is the only method that would work for me (25 XLT Hybrid). Still want to get in a few more fill ups in before adjusting. Currently I am looking at ~887 for my number

Good day, Ferta

I am so glad you found it useful and it worked for you!

After I did my adjustments on my truck, I also waited to do several fills of the gas tank. Make sure you get it down till you have about a 1/4 tank remaining to give the truck plenty of time to figure out your driving style as well as to get a proper fuel mileage average.

I manually track every tank of fuel, date fuelling occurs, total mileage, trip, liters added and the trucks estimated fuel mileage as well. I keep it in a little book in the center console with a mechanical pencil for note taking.

I can really see the difference in the trucks mileage estimates so I don't go too far, either way.

It will never be spot on but if it is close then I am satisfied.

Take care and happy Mavericking!

Andy

 

[bsenecal]

I'm totally frustrated! Can't get my 2024 hybrid XLT into ET mode using any of the above mentioned methods. Is there a way to adjust the AFE bias using FORScan?

You are not alone after numerous unsuccessful attempts I have just decided to do it the old fashioned way dividing the total miles driven since the last fill up by the amount I put in.
I am super happy with the mileage I get but the Maverick tries to make me think it’s even 5-7% better .
Brian

 

[doug maverick]

2023 XLT Hybrid does not seem to have any way to access engineering mode. There was a YouTube guy that has a 2022 Lariat, but so far I've not found a 2023 XLT Hyrbid person that has been able to use engineering mode.

Has anyone with an older Hybrid been able to do so?

 

[HeyBales]

2023 XLT Hybrid does not seem to have any way to access engineering mode. There was a YouTube guy that has a 2022 Lariat, but so far I've not found a 2023 XLT Hyrbid person that has been able to use engineering mode.

Has anyone with an older Hybrid been able to do so?

Tons. At the bottom of this page is 5 Similar threads. You'll see there also that older ones can access it.
Shoot - it started with older ones because no 24 existed yet!

 

[doug maverick]

I've actually read most of those threads, and none of those ways works in my truck. I press the OK button before I turn the key, I hold the OK button, for up to 15 seconds, and nothing happens. I've tried turning the key all the to the start position, and I've tried the just On position. Still nothing. I tried holding the brake pedal, or not holding the brake before turning the key.

I have a key style, not a push button. I saw the note that it shouldn't matter, and I know the difference between ON and Start. My truck has the older style instrument cluster, with mechanical Temp and Fuel gauges. Still would love to find a way to get into EM mode.

Sponsored