2021 HONDA RIDGELINE check engine

415
uuWhen Driving uIntelligent Variable Torque Management (i-VTM4TM) AWD System*
Driving
Intelligent Variable Torque Management (i-VTM4TM)
AWD System*
The Intelligent Variable To rque Management (i-VTM4TM) AWD System is a full time
all wheel drive system that automatically controls and transfers varying amount of
engine torque to all wheels independently according to the driving conditions.
You still need to exercise the same care when accelerating, steering, and braking
that you would in a two wheel drive vehicle.
Avoid continuously driving on slippery surfaces where a wheel is likely to spin out,
and do not drive if the All-wheel drive ( AWD) Indicator starts blinking. Driving
continuously under such conditions can damage the system’s torque distribution
unit.
If the All-wheel drive (AWD ) Indicator blinks while driving, it indicates the
differential temperature is too high. If this happens, pull to the side of the road
when it is safe, shift to park, and idle the engine until the indicator goes out. If the
indicator does not go out, take your vehi cle to a dealer to have it checked.1Intelligent Variable Torq ue Management (i-VTM4TM) AWD
System*
NOTICE
Do not continuously spin the front tires of your
vehicle. Continuously spinning the front tires can
cause transmission or re ar differential damage.
The Intelligent Variable Torque Management (i-
VTM4
TM) AWD System may not function properly if
tire type and size are mixed. Make sure to use the
same size and type of tire , and the air pressures as
specified. 2 Tire and Wheel Replacement P. 522
* Not available on all models

Continued429
uuHonda Sensing ®u Collision Mitigation Braking SystemTM (CMBSTM)
Driving
Press and hold the butt on until the beeper
sounds to switch the system on or off.
When the CMBS
TM is off:
• The CMBSTM indicator in the instrument
panel comes on.
• A message on the multi-information display
reminds you that the system is off.
The CMBS
TM is turned on every time you start
the engine, even if you turned it off the last
time you drove the vehicle.
■CMBSTM On and Off1 Collision Mitigation Braking SystemTM (CMBSTM)
The CMBS
TM may automatically shut off, and the
CMBSTM indicator will come and stay on under certain
conditions:
2 CMBS
TM Conditions and Limitations P. 430
Have your vehicle checked by a dealer if you find any
unusual behavior of the system (e.g., the warning
message appears too frequently).

469
uuBraking uBrake System
Driving
Your vehicle is equipped with disc brakes at all four wheels. A vacuum power assist
helps reduce the effort needed on the brake pe dal. The brake assist system increases
the stopping force when you depress the brake pedal hard in an emergency
situation. The anti-lock brake system (ABS) helps you retain steering control when
braking very hard.
2 Brake Assist System P. 471
2 Anti-lock Brake System (ABS) P. 470
■Foot Brake1Foot Brake
Check the brakes after driving through deep water,
or if there is a buildup of road surface water. If
necessary, dry the brakes by lightly depressing the
pedal several times.
If you hear a continuous me tallic friction sound when
applying the brakes, this is caused by the brake wear
indicator rubbing on the brake rotor and indicates
that the brake pads need to be replaced. Have the
vehicle checked by a deal er. If you hear only an
occasional squeak or squeal when you initially apply
the brake pedal, this may be normal and caused by
high frequency vibr ation of the brake pads against
the rotating brake disc.
Constantly using the brake pedal while going down a
long hill builds up heat, which reduces the brake
effectiveness. Apply engine braking by taking your
foot off the accelerator pe dal and downshifting to a
lower gear.
Do not rest your foot on the brake pedal while
driving, as it will lightly apply the brakes and cause
them to lose effectiveness over time and reduce pad
life. It will also conf use drivers behind you.

470
uuBraking uAnti-lock Brake System (ABS)
Driving
Anti-lock Brake System (ABS)
Helps prevent the wheels from locking up, a nd helps you retain steering control by
pumping the brakes rapidly, much faster than you can.
The electronic brake distribution (EBD) system, which is part of the ABS, also
balances the front-to-rear braking distri bution according to vehicle loading.
You should never pump the brake pedal. Let the ABS work for you by always
keeping firm, steady pressure on the brake pe dal. This is sometimes referred to as
“stomp and steer.”
■ABS operation
The brake pedal may pulsate slightly when the ABS is working. Depress the brake
pedal and keep holding the pedal firmly dow n. On dry pavement, you will need to
press on the brake pedal very hard before the ABS activates. However, you may feel
the ABS activate immediately if yo u are trying to stop on snow or ice.
ABS may activate when you depress the brake pedal when driving on:
• Wet or snow covered roads.
• Roads paved with stone.
• Roads with uneven surfaces, such as potholes, cracks, manholes, etc.
When the vehicle speed goes unde r 6 mph (10 km/h), the ABS stops.
■ABS1Anti-lock Brake System (ABS)
NOTICE
The ABS may not function correctly if you use a tire of
the wrong size or type.
If the ABS indicator comes on while driving, there
may be a problem with the system.
While normal braking will not be affected, there is a
possibility that the ABS wi ll not be operating. Have
your vehicle checked by a dealer immediately.
The ABS is not designed for the purpose of reducing
the time or distance it takes for a vehicle to stop: It is
designed to limit brake lo ckup which can lead to
skidding and loss of steering control.
In the following cases, yo ur vehicle may need more
distance to stop than a vehicle without the ABS:
•You are driving on rough or uneven road surfaces,
such as gravel or snow.
•The tires are equipped with tire chains.
The following may be observed with the ABS system:
•Motor sounds coming from the engine
compartment when the brakes are applied, or
when system checks are being performed after the
engine has been started and while the vehicle
accelerates.
•Brake pedal and/or the vehicle body vibration when
ABS activates.
These vibrations and sounds are normal to ABS
systems and are no cause for concern.

487
Maintenance
This chapter discusses basic maintenance.
Before Performing MaintenanceInspection and Maintenance ............ 488
Safety When Performing Maintenance ... 489
Parts and Fluids Used in Maintenance Service ........................................... 490
Maintenance Minder
TM..................... 491
Maintenance Under the Hood Maintenance Items Under the Hood .... 496
Opening the Hood ........................... 497
Engine Compartment Cover ............. 498
Recommended Engine Oil ................ 499
Oil Check ......................................... 500
Adding Engine Oil ............................ 501
Changing the Engine Oil and Oil Filter ...502 Engine Coolant ................................ 504
Transmission Fluid ............................ 506
Brake Fluid ....................................... 507
Refilling Window Wa
sher Fluid......... 507
Replacing Light Bulbs ....................... 508Checking and Maintaining Wiper
Blades .......................................... 514
Checking and Maintaining Tires
Checking Tires ................................. 516
Tire and Loading Information Label ... 517
Tire Labeling .................................... 517
DOT Tire Quality Grading (U.S. Vehicles) .... 519Wear Indicators................................ 521 Tire Service Life ................................ 521
Tire and Wheel Replacement ........... 522
Tire Rotation .................................... 523
Winter Tires ..................................... 524
Battery ............................................... 525
Remote Transmitter Care Replacing the Button Battery ........... 527
Climate Control System Maintenance.......528CleaningInterior Care .................................... 529
Exterior Care.................................... 531
Accessories and Modifications ........ 535

494
uuMaintenance MinderTMuTo Use Maintenance MinderTM
Maintenance
■Maintenance Service Items1Maintenance Service Items
•Independent of the maintenance message in the
multi-information display, replace the brake fluid
every 3 years.
•Adjust the valves during services A, B, 1, 2, or 3 if
they are noisy.
Maintenance Minder MessageSystem Message
Indicator
Sub Items
Main
Item
*1: If the message Maintenance Due Now does not appear more than 12 months after the display
is reset, change the engine oil every year.
# : See information on maintenance and emissions warranty in the first column on page 581.
*2: If you drive in dusty conditions, replace the air cleaner element every 15,000 miles (24,000 km).
*3: If you drive primarily in urban areas that have high concentrations of soot in the air from industry and from diesel-powered vehicles, replace every 15,000 miles (24,000 km).
CODEMaintenance Main Items
A
●Replace engine oil*1
B●Replace engine oil*1 and oil filter●Inspect front and rear brakes●Check parking brake adjustment●Inspect tie rod ends, steering gearbox, and boots●Inspect suspension components●Inspect driveshaft boots●Inspect brake hoses and lines (Including ABS/VSA ®)●Inspect all fluid levels and condition of fluids●Inspect exhaust system#
●Inspect fuel lines and connections#
*4: Driving in mountainous areas at very low vehicle speeds or trailer towing results in higher transmission
temperatures. This requires transmission fluid changes more frequently than recommended by the
Maintenance Minder
TM. If you regularly drive your vehicle under these conditions, have the transmission
fluid changed at every 30,000 miles (48,000 km) or 2 years.
*5: If you drive regularly in very high temperatures (over 110°F, 43°C), in very low temperatures (under
-20°F, -29°C), or towing a trailer, replace every 60,000 miles (U.S.) / 100,000 km (Canada).
*6: Driving in mountainous areas at very low vehicle speeds or trailer towing results in higher level of mechanical (Shear) stress to fluid. This requires differential fluid changes more frequently than
recommended by the Maintenance Minder
TM. If you regularly drive your vehicle under these conditions,
have the differential fluid changed at 7,500 miles (12,000 km), then every 15,000 miles (24,000 km).
CODEMaintenance Sub Items
1
●Rotate tires
2●Replace air cleaner element*2
●Replace dust and pollen filter*3
●Inspect drive belt
3
●Replace transmission fluid and transfer fluid*, *4
4●Replace spark plugs●Replace timing belt and inspect water pump*5
●Inspect valve clearance
5
●Replace engine coolant
6●Replace rear differential fluid*, *6
* Not available on all models

497
uuMaintenance Under the Hood uOpening the Hood
Maintenance
Opening the Hood
1. Park the vehicle on a level surface, and set
the parking brake.
2. Pull the hood release handle under the
driver’s side lower left corner of the
dashboard.
u The hood will pop up slightly.
3. Push the hood latch lever (located under
the front edge of the hood to the center) to
the side and raise the hood. Once you have
raised the hood slightly, you can release the
lever.
4. Remove the support rod from the clamp
using the grip. Mount the support rod in
the hood.
When closing, remove the support rod, and
stow it in the clamp, then gently lower the
hood. Remove your hand at a height of
approximately 12 inches (30 cm) and let the
hood close.1 Opening the Hood
NOTICE
Do not open the hood when the wiper arms are
raised.
The hood will strike the wipe rs, resulting in possible
damage to the hood and/or the wipers.
NOTICE
Do not press the engine cover forcibly. This may
damage the engine cover and component parts.
When closing the hood, check that the hood is
securely latched.
If the hood latch lever moves stiffly, or if you can
open the hood without lifti ng the lever, the latch
mechanism should be cl eaned and lubricated.
Do not open the hood while the Auto Idle Stop
function is activated.
Hood Release Handle
Pull
Lever
Support RodGrip
Clamp

500
uuMaintenance Under the Hood uOil Check
Maintenance
Oil Check
We recommend that you check the engi ne oil level every time you refuel.
Park the vehicle on level ground.
Wait approximately three minutes after turn ing the engine off before you check the
oil. 1.Remove the dipstick (orange).
2. Wipe the dipstick with a clean cloth or
paper towel.
3. Insert the dipstick back all the way into its
hole.
4. Remove the dipstick again, and check the
level. It should be between the upper and
lower marks. Add oil if necessary.1Oil Check
If the oil level is near or below the lower mark, slowly
add oil, being carefu l not to overfill.
Lower MarkUpper Mark