What do i do when oil maintenance required message shows? any immediate risk?

replace oil level sensor

The maintenance required light does not indicate any problem with the engine or systems like a Check Engine Light (CEL) does. This light is normally a reminder to change the oil. Getting the light to turn off is really easy.

In order, follow these steps:

1. Press and hold down the trip odometer reset button.
2. Turn the key to the on position without starting the engine.
3. Continue to hold down the reset button; The light should go out within 10-15 seconds.

God bless and good luck.

there is no light for emissions testing on this vehicle. there is a ses light that can come on, indicationg a problem with the engine or transmission electronic system. this will require a scan tool to pull trouble codes. there is another light called oil life monitoring that needs to be reset after oil changes, which I suspect is what you are seeing. here is a picture of the light and the instructions for resetting.,

The Engine Oil Life System calculates when to change your engine oil and filter based on vehicle use. Anytime your oil is changed, reset the system so it can calculate when the next oil change is required. If a situation occurs where you change your oil prior to a CHANGE OIL SOON message being turned on, reset the system.
After changing the engine oil, the system must be reset as follows:

1. Turn the ignition to RUN, with the engine OFF.
2. Press the information and reset buttons on the Driver Information Center (DIC) at the same time to enter the personalization menu.
3. Press the information button to scroll through the available personalization menu modes until the DIC display shows OIL LIFE RESET.
4. Press and hold the reset button until the DIC display shows ACKNOWLEDGED. This will tell you the system has been reset.
5. Turn the key to LOCK.

If the CHANGE ENGINE OIL message comes back on when you start the vehicle, the Engine Oil Life System has not reset. Repeat the reset procedure.

this light can come on even thought service is not actually due. if the service was performed and the light was not on at the time, sometimes you cannot reset them if they are not actually lit, or 99% of the time the technician forgets if the light was not on. stop by your shop and they can reset it for you in just a few moments, and for no charge. good luck!

The instructions on how to reset the' oil change required' message is in the owners manual (I believe it's page 81). Listed below is a site to get a free download of the manual for your 05 Mountaineer. Let me know if you have any trouble accessing this info.
https://www.fleet.ford.com/maintenance/owners_manuals/results.asp

With ignition off, press and hold "SELECT" and "RESET" buttons on dash and turn ignition to the "ON" position. Continue to hold until lamp resets.

a major service is due at 60000 miles. the light is just a reminder that maintenance is due. is it the message on the nav screen or the one on the dash cluster? if you want to turn it of, hold the trip/od button in while turning the ignition on, keep your foot off the brake, dont start the car. you will see dashes flashing where the od shows miles, hold until its done flashing. and the lite on the dash cluster will go out. it will come back on after 5000 miles. you can go online to lexus.com to review what the services are and what they involve.

Check the engine oil level. if low add 1/2 quart and re check untill full. GO get oil change. DO NOT RUN if oil is not showing on the dip stick. The oil weight is in the owners manual.

Please note:

Honda makes reference to proper vehicle maintenance in their service/user manual. Consult your authorized Honda dealer before doing anything that may void your vehicle warranty.

https://techinfo.honda.com/rjanisis/pubs/om/AC0606/AC0606O00192A.pdf

Owner's Manual page 193-197.

Resetting the Engine Oil Life
Indicator

Your dealer will reset the display
after completing the required
maintenance service. You will see
‘‘OIL LIFE 100 %’’ on the odometer/
trip meter display the next time you
turn the ignition switch to the ON
(II) position.

If maintenance service is done by
someone other than your dealer,
reset the maintenance minder as
follows:

1. Turn the ignition switch to the ON
(II) position.

2. Press the Select/Reset knob until
the engine oil life indicator is
displayed.

3. Press the Select/Reset knob for
more than 10 seconds. The engine
oil life indicator and the
maintenance item code(s) will
blink.

4. Press the Select/Reset knob for
more than 5 seconds. The
maintenance items code(s) will
disappear, and the engine oil life
will reset to ‘‘100.’’

Important Maintenance
Precautions

If you have the required service
done but do not reset the display, or
reset the display without doing the
service, the system will not show the
proper maintenance intervals. This
can lead to seriousmechanical
problems because you will no longer
have an accurate record of when
maintenance is needed.
Your authorized Honda dealer
knows your vehicle best and can
provide competent, efficient service.
However, service at a dealer is not
mandatory to keep your warranties
in effect. Maintenance may be done
by any qualified service facility or
person who is skilled in this type of
automotive service. Make sure to
have the service facility or person
reset the display as previously
described. Keep all receipts as proof
of completion, and have the person
who does the work fill out the
maintenance record. Check your
warranty booklet for more
information.

Information obtained from:

https://techinfo.honda.com/rjanisis/RJAAI001_OMANUAL.ASP?YEAR=2006

If the information provided to you was useful, please rate my response.

Thanks,

OpenSource13

Read the Manual that came with the car. It will tell you how to turn the maintenance signal off. Cant remember, been a while since ive done it. But i know 100% its in the manual.