Yaw Rate

Yaw Rate
This diagnostic checks the yaw rate sensor in the control unit. This device detects when the vehicle turns, and repositions the vehicle position icon on the map screen. For more detailed information, see the yaw rate sensor theory of operation under "System Description".

- "Sensor" indicates the voltage output from the yaw rate sensor. It should indicate about 2.500 volts when stopped.
- "Offset" is the reference voltage or standard within the yaw rate sensor. It also should indicate about 2.500 volts when stopped.
- A "sensor" output voltage HIGHER than the "Offset" voltage indicates that the vehicle is turning to the right.
A "sensor" output voltage LOWER than the "Offset" voltage indicates that the vehicle is turning to the left.
- The yaw rate offset and sensor should both indicate about 2.500 volts when stopped. If either reads zero or 5.000 volts, replace the navigation unit.
- The yaw rate offset and sensor should be within +/- 0.01 V of each other when stopped. The sensor value should change relative to the offset as the car is turned while driving. If not, replace the navigation unit.

Example: Vehicle stopped

Normal Abnormal
Offset 2.526 V Offset 2.526 V
Sensor 2.516-2.536 V Sensor 2.623 V

Example: Vehicle turning

Normal Abnormal

Offset 2.526 V Offset 2.526 V
Sensor 2.678 V Sensor 2.623 V
(right turn) (no change on
2.478 V turns)
(left turn)

- Auto tuning should always be on. If it is off, turn it on.
- "Sensitivity study" represents the status of the internal tuning function. At initialization, this value starts at 6 and increases to # 10 as the internal correction values become more accurate.
- The settings "CCW Cal Factor", "CW Cal Factor", and "Set" are for factory use only. THIS SHOULD NEVER BE USED.

NOTE: Do not try to tune the yaw rate sensor without instructions from American Honda.

Yaw Rate Tuning

This diagnostic allows you to graphically display problems with the yaw rate sensor.

- The "ANG-Disp" value accumulates any differences between the "offset", and "sensor" voltages (see Yaw Rate diagnostic). When the sensor is healthy, the random changes in these two voltage generally cancels out, so the value is 0. However if one voltage is consistently higher than the other, then the "ANG-Disp" value accumulates the constant change.
- The "Reset" button temporarily clears the angular accumulation (ANG-Disp), and clears the display dots.
- Do not touch the "CCW" or "CW", or "Set" buttons. These are used for factory setup only.

For gross problems with the sensor, the stationary test usually confirms whether the sensor is defective. For yaw rate issues related to driving, perform the road test described.

1. Stationary test: If the "VP" icon spins in place and the "ANG-Disp" value slowly increases or decreases in value, the yaw rate sensor is defective. Replace the Navigation control unit.
2. Road test: Drive the vehicle on a very straight road. Enter the diagnostic mode, select "Yaw rate", and touch the "Tuning" button. While driving down a straight road, the white "dots" should trace a straight line across the screen. However, if you are driving on a straight road, and you notice the dots constantly dropping down or heading up as, you drive, the navigation control unit's yaw sensor is defective. You can touch "Reset" to clear "ANG-Disp", and dotted line.




3. If either test fails, please enter "Yaw rate sensor defective" for the problem description, on the "Navigation core return form".