Acura 3.5 RL, Manual

Page: 1305 / 1453

Navigation System
General Troubleshooting Information
General Operation
Refer to the Acura Navigation System Owner's manual
for the navigation system operating procedures.
Anti-theft Feature
The navigation system has a coded theft protection cir-
cuit. Be sure to get the customer's 4-digit security code
number before:
• disconnecting the battery
• disconnecting the navigation unit 8P connector
• removing the No. 56 (7.5A) fuse from the under-hood
fuse/relay box
After service, reconnect power to the navigation unit,
and turn the ignition switch ON (II). Enter the 4-digit
security code, then select "Done".
If the code cannot be found, use the interactive Network
(
i N) to look it up. You will need the serial number for
the navigation unit in the trunk. It is on a tag on the
underside of the unit. Alternatively, you can view the
serial number in one of the Navi ECU diagnostic
screens.
When replacing the navigation unit, be sure to give the
customer the new anti-theft security code.
Symptom Diagnosis
Under some circumstances, the navigation system may
behave in an inconsistent manner. Some customers may
think that this indicates a problem when, in fact, the
system is working properly. Keep the following items in
mind when interviewing customers about symptoms
of the navigation system.
Self-lnertial Navigation Limitations
When GPS signals cannot be received (like in a tunnel or
in an urban environment of tall buildings), the system is
totally dependant on the yaw rate and speed sensor to
position the vehicle oh the map. Under these circum-
stances small errors in the yaw rate and speed sensor
can accumulate and display the vehicle position on an
adjacent street, or lagging behind the actual position.
This is normal, and usually corrects itself once sate-
llite reception is re-established.
The following circumstances may causes vehicle posi-
tioning errors.
• Moving the vehicle with the navigation system on and
the vehicle stopped, such as by ferry or tow truck, or if
the vehicle is spun on a turn table
• Tire slippage, changes in tire rolling diameters, and
some driving situations may cause discrepancies in
travel distances. Examples of this include:
- Continuous tire slippage on a slippery surface
- Driving with snow chains mounted
-Abnormal tire pressure
- Incorrect tire size
- Frequent lane changes across a wide highway
-Continuous driving on a straight or gently curving
highway
• Tolerances in the system and map inaccuracies some-
times limit how precisely the vehicle position is indi-
cated. Examples of this include:
- Driving on roads not shown on the map (map match-
ing is not possible)
- Driving on a road that winds in one direction, such as
a loop bridge, an interchange, or a spiral parking
garage
-Driving on a road with a series of sharp hair-pin
turns
- Driving near a gradual highway exit or transition
- Driving on one of two close parallel roads
- Making many 90 degree turns
Global Positioning System (GPS) Limitations
The GPS cannot detect the vehicle's position during the
following instances:
• For the first 5 to 10 minutes after reconnecting the bat-
tery (this can take as long as 45 minutes)
• When the satellite signals are blocked by tall building,
mountains, tunnels, large trees, or large trucks
• When there is no satellite signal output (Signal output
is sometimes stopped for satellite servicing)
• When the satellite signals are blocked by the operation
of some electronic aftermarket accessories including,
but not limited to non-DEM in-dash entertainment
units (radio, CD players/changers, and Lo Jack) and
window tinting above the GPS antenna
The accuracy of GPS is reduced during these instances:
• When only two satellite signals can be received (Three
satellite signals are required for accurate positioning)
• When the satellite control centers are experiencing
problems
• When driving hear high tension power lines.
• When driving near tall buildings that reflect satellite
signals, creating false position location readings.
• If electronic GPS jamming is occurring either inten-
tionally, or unintentionally.
• If loose items or pets are resting above the antenna
on the rear shelf.