2011 Acura MDX ignition

Diagnosing why the engine won't
start falls into two areas, depending
on what you hear when you turn the
ignition switch to the START (III)
position:●
You hear nothing, or almost
nothing. The engine's starter
motor does not operate at all, or
operates very slowly.
●
You can hear the starter motor
operating normally, or the starter
motor sounds like it is spinning
faster than normal, but the engine
does not start up and run.
Nothing Happens or the Starter
Motor Operates Very Slowly
When you turn the ignition switch to
the START (III) position, you do not
hear the normal noise of the engine
trying to start. You may hear a
clicking sound, a series of clicks, or
nothing at all. Check these things:
●
Check the transmission interlock.
The transmission must be in Park
or neutral or the starter will not
operate.
●
Turn the ignition switch to the ON
(II) position. Turn on the
headlights, and check their
brightness. If the headlights are
very dim or do not come on at all,
the battery is discharged. See
Jump Starting
on page 552.
●
Turn the ignition switch to the
START (III) position. If the
headlights do not dim, check the
condition of the fuses. If the fuses
are OK, there is probably
something wrong with the
electrical circuit for the ignition
switch or starter motor. You will
need a qualified technician to
determine the problem. See
Emergency Towing on page 566.If the headlights dim noticeably or
go out when you try to start the
engine, either the battery is
discharged or the connections are
corroded. Check the condition of
the battery and terminal
connections (see page 541). You
can then try jump starting the
vehicle from a booster battery (see
page 552).
The Starter Operates Normally
In this case, the starter motor's speed
sounds normal, or even faster than
normal, when you turn the ignition
switch to the START (III) position,
but the engine does not run.
●
Are you using a properly coded
key? An improperly coded key will
cause the immobilizer system
indicator in the instrument panel
to blink rapidly (see page 72).
CONTINUED
If the Engine Won't Start
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If this indicator comes on
while driving, it means one
of the engine's emissions control
systems may have a problem. Even
though you may feel no difference in
your vehicle's performance, it can
reduce your fuel economy and cause
increased emissions. Continued
operation may cause serious damage.
If you have recently refueled your
vehicle, the indicator coming on
could be due to a loose or missing
fuel fill cap. Tighten the cap until it
clicks at least once. Tightening the
cap will not turn the indicator off
immediately; it can take several days
of normal driving. If the indicator comes on repeatedly,
even though it may turn off as you
continue driving, have your vehicle
checked by the dealer as soon as
possible.
If you keep driving with the malfunction
indicator lamp on, you can damage
your vehicle's emissions controls and
engine. Those repairs may not be
covered by your vehicle's warranties.
You will also see a
‘‘CHECK
EMISSION SYSTEM ’’message on
the multi-information display (see
page 86).
Readiness Code
Your vehicle has certain ‘‘readiness
codes ’’that are part of the on-board
diagnostics for the emissions systems. In
some states, part of the emissions testing
is to make sure these codes are set. If
they are not set, the test cannot be
completed.
If the battery in your vehicle has been
disconnected or gone dead, these codes
may be erased. It takes several days of
driving under various conditions to set
the codes again.
To check if they are set, turn the ignition
switch to the ON (II) position, without
starting the engine. The malfunction
indicator lamp will come on for 20
seconds. If it then goes off, the readiness
codes are set. If it blinks five times, the
readiness codes are not set. If possible,
do not take your vehicle for an emissions
test until the readiness codes are set.
Refer to Emissions Testing for more
information (see page 583).Malfunction Indicator Lamp
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U.S. Canada
The brake system
indicator normally
comes on when you turn the ignition
switch to the ON (II) position, and as
a reminder to check the parking
brake. It will stay on if you do not
fully release the parking brake.
If the brake system indicator comes
on while driving, the brake fluid level
is probably low. Press lightly on the
brake pedal to see if it feels normal. If
it does, check the brake fluid level
the next time you stop at a service
station (see page 519).
You will also see a ‘‘LOW BRAKE
FLUID ’’message on the multi-
information display (see page 86). If the fluid level is low, take your
vehicle to a dealer, and have the
brake system inspected for leaks or
worn brake pads.
However, if the brake pedal does not
feel normal, you should take
immediate action. A problem in one
part of the system's dual circuit
design will still give you braking at
two wheels. You will feel the brake
pedal go down much farther before
the vehicle begins to slow down, and
you will have to press harder on the
pedal.
You will also see a
‘‘CHECK BRAKE
SYSTEM ’’message on the multi-
information display (see page 86). Slow down by shifting to a lower
gear, and pull to the side of the road
when it is safe. Because of the long
distance needed to stop, it is
hazardous to drive the vehicle. You
should have it towed, and repaired as
soon as possible (see
Emergency
Towing on page 566).
If you must drive the vehicle a short
distance in this condition, drive
slowly and carefully.
If the ABS indicator and the VSA
system indicator come on with the
brake system indicator, have your
vehicle inspected by your dealer
immediately.
Brake System Indicator55810/06/29 11:59:04 11 ACURA MDX MMC North America Owner's M 50 31STX640 enu

The secondary fuse box is on the
passenger's side.
To open it, push the tabs as shown.
U.S. Advance Package, AdvancePackage with Entertainment, andCanadian Elite Package modelsThe sub fuse box is on the
passenger's side.
To open it, push the tabs as shown. Checking and Replacing Fuses
If something electrical in your
vehicle stops working, the first thing
you should check for is a blown fuse.
Determine from the chart on pages
563, 564, and 565, or the diagram on
the fuse box lid, which fuse or fuses
control that device. Check those
fuses first, but check all the fuses
before deciding that a blown fuse is
the cause. Replace any blown fuses,
and check if the device works.
1. Turn the ignition switch to the
LOCK (0) position. Make sure the
headlights and all other
accessories are off.
2. Remove the cover from the fuse box.
UNDER-HOOD (SECONDARY)
TAB
UNDER-HOOD (SUB)
TAB
Fuses56010/06/29 11:59:04 11 ACURA MDX MMC North America Owner's M 50 31STX640 enu

PRIMARY UNDER-HOOD FUSE BOX
No. Amps. Circuits Protected1 120 A Main fuse － Not Used
2 － 1 － Not Used
2 － 2 30 A SH-AWD
2 － 3 30 A Rear Blower Motor
2 － 4 40 A ABS VSA
2 － 5 40 A Trailer Main
2 － 6 40 A Power Seats, Driver's Position
Memory System, Subwoofer,
Telescopic Steering Wheel
2 － 7 40 A Front Heated Seat, TPMS,
Moonroof, Driver's Lumbar
Support
2 － 8 － Not Used
3 － 1 60 A Fog Lights, Front Blower
Motor, Interior Light
3 － 2 40 A Headlights, Daytime Running
Lights
3 － 3 60 A Cooling Fan, Condenser Fan,
MG Clutch, Headlight
Washer
ꭧ1
3－ 4 50 A Ignition Switch Main
ꭧ 1: Canadian model
ꭧ 2: If equipped No. Amps. Circuits Protected
3 － 5 50 A Power Window
3 － 6 60 A Power Tailgate Opener/Closer,
Rear ACC Socket, Interior
Light,
Rear Defroster
3 － 7 30 A ECU (PCM)
3 － 8 30 A TECH
4 40 A Audio, Door Lock, Interior Lights, Front ACC Socket
5 30 A EPT-L
ꭧ 2
6 30 A EPT-R
ꭧ2
7 30 A Active Damper Control Unit
ꭧ2
8 30 A Audio Amplifier
9 7.5 A Battery Sensor
10 15 A Hazard
11 15 A Horn, Stop
12 20 A ABS VSA
13 20 A Trailer (Brake)
14 20 A Rear Heated Seat
ꭧ 2
15 20 A A/C Inverter
CONTINUED
Fuse Locations
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Onboard Refueling Vapor
Recovery
The onboard refueling vapor
recovery (ORVR) system captures
the fuel vapors during refueling. The
vapors are adsorbed in a canister
filled with activated carbon. While
driving, the fuel vapors are drawn
into the engine and burned off.
Exhaust Emissions Controls
The exhaust emissions controls
include four systems: PGM-FI,
ignition timing control, exhaust gas
recirculation, and three way catalytic
converter. These four systems work
together to control the engine's
combustion and minimize the
amount of HC, CO, and NOx that
come out the tailpipe. The exhaust
emissions control systems are
separate from the crankcase and
evaporative emissions control
systems.
PGM-FI SystemThe PGM-FI system uses sequential
multiport fuel injection. It has three
subsystems: air intake, engine
control, and fuel control. The
powertrain control module (PCM)
uses various sensors to determine
how much air is going into the
engine. It then controls how much
fuel to inject under all operating
conditions.Ignition Timing Control SystemThis system constantly adjusts the
ignition timing, reducing the amount
of HC, CO, and NOx produced.Exhaust Gas Recirculation (EGR)SystemThe exhaust gas recirculation (EGR)
system takes some of the exhaust
gas and routes it back into the intake
manifold. Adding exhaust gas to the
air/fuel mixture reduces the amount
of NOx produced when the fuel is
burned.
Three Way Catalytic ConverterThe three way catalytic converter is
in the exhaust system. Through
chemical reactions, it converts HC,
CO, and NOx in the engine's exhaust
to carbon dioxide (CO
2), nitrogen
(N
2), and water vapor.
Replacement Parts
The emissions control systems are
designed and certified to work
together in reducing emissions to
levels that comply with the Clean Air
Act. To make sure the emissions
remain low, you should use only new
Acura replacement parts or their
equivalent for repairs. Using lower
quality parts may increase the
emissions from your vehicle.
The emissions control systems are
covered by warranties separate from
the rest of your vehicle. Read your
warranty manual for more
information.
Emissions Controls
581
Technical Information
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A
Accessories andModifications
..........................
426
ACCESSORY (Ignition Key Position)
.................................
138
Accessory Power Sockets
..........
175
AC Power Outlet
........................
176
Active Damper System
...............
478
Active Head Restraints
...............
151
AcuraLink
®(U.S. models
only)
.......................................
398
Adaptive Cruise Control (ACC)
.....................................
345
Additives, Engine Oil
.................
512
Adjusting the Steering Wheel
....
133
Advanced Airbags
........................
30
Airbag (SRS)
..........................
10, 26
Air Conditioning System
............
180
Rear A/C Control
....................
185
Air Outlets (Vents)
.....................
187
Air Pressure, Tires
..............
534, 535
Alcohol in Gasoline
....................
418
Antifreeze
...................................
514 Anti-lock Brakes (ABS)
Indicator
............................
68, 456
Operation
................................
455
Anti-theft, Audio System
.............
305
Anti-theft Steering Column Lock
.......................................
138
Audio System
......................
190, 209
Automatic Climate Control.........
181
Automatic Lighting Off Feature
...................................
130
Automatic Seat Belt Tensioners...
23
Automatic Speed Control
...........
342
Automatic Transmission
............
437
Capacity, Fluid
........................
572
Checking Fluid Level
..............
517
Driving with the Paddle Shifters
................................
441
Shifting
...................................
438
Shift Lever Position Indicators
............................
437
Shift Lever Positions
...............
438
Shift Lock Release
...................
440
Auxiliary Input Jack
...................
304 B
Battery
Charge Low
..............................
82
Charging System Indicator
........................
67, 556
Jump Starting
..........................
552
Maintenance
...........................
541
Specifications
..........................
573
Before Driving
...........................
417
Belts, Seat
................................
9, 21
Beverage Holders
......................
172
Blind Spot Information System (BSI)
......................................
470
Bluetooth
®Audio
.......................
295
Bluetooth
®HandsFreeLink
®
......
362
Booster Seats
...............................
57
CONTINUED
Index
I
INDEX
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Octane Requirement
...............
418
Tank, Refueling
.......................
419
Gas Station Procedures
..............
419
Gauges
Engine Coolant Temperature...
76
Fuel
..........................................
76
Speedometer
............................
76
Tachometer
..............................
76
GAWR (Gross Axle Weight Rating)
...................................
482
GCWR (Gross Combined Weight Rating)
...................................
482
Gearshift Lever Positions Automatic Transmission
...............
437, 438
Glove Box
..................................
173
Gross Axle Weight Rating (GAWR)
.................................
482
Gross Vehicle Weight Rating (GVWR)
.................................
482
GVWR (Gross Vehicle Weight
Rating)
...................................
482 H
Halogen Headlight Bulbs
...........
521
HandsFreeLink
®
........................
362
Hazard Warning Flashers
..........
131
Headlights
.................................
127
Aiming
....................................
521
Automatic Lighting Off
............
130
Daytime Running Lights
.........
129
High Beam Indicator
................
72
High Beams, Turning on
.........
127
Lights On Indicator
..................
72
Low Beams, Turning on
..........
127
Reminder Chime
.....................
128
Replacing Halogen Bulbs
........
521
Turning on
..............................
127
Washers
..................................
126
Headphones
...............................
335
Head Restraints
..........................
149
Heated Mirror
............................
165
Heaters, Seats
............................
156
Heating and Cooling
..................
180
High Altitude, Starting at
............
436
High Beam Lever
................
127, 128
High-Low Beam Switch
..............
127 HomeLink
®Universal
Transceiver
............................
360
Hood, Opening and Closing the
..........................................
421
Horn
......................................
4, 124
I
Identification Number, Vehicle
...................................
570
Ignition Keys
........................................
135
Switch
.....................................
138
Timing Control System
...........
581
Immobilizer System
...................
137
Important Safety Precautions
.........
6
CONTINUED
Index
V
INDEX
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