How to Troubleshoot the VSA System (With VSA)

How to Troubleshoot the VSA System

System Indicator

This system has four indicators: ABS indicator (A), VSA indicator (B), VSA activation indicator (C) and brake system indicator (D). When the system detects a problem, it illuminates the appropriate indicators. Depending on the failure, the control unit determines which indicators are turned on.

When ABS function is lost:
ABS indicator, VSA indicator and VSA activation indicator turn on.
When VSA function is lost:
VSA indicator and VSA activation indicator turn on.
When all functions are lost:
All four indicators turn on.

ABS/VSA Indicator

If the system is OK, the ABS and VSA indicators will go off 2 seconds after turning the ignition switch ON (II).
The ABS and VSA indicators come on when the control unit detects a problem in the system. However, even though the system is operating properly, the indicator may come on under these conditions:
- Only the drive wheel rotates.
- One drive wheel is stuck.
- The vehicle goes into a spin.
- The ABS or VSA continues to operate for a long time.
- The vehicle is subjected to an electrical signal disturbance.

To determine the actual cause of the problem, question the customer about the problem, taking these conditions into consideration.

When a problem is detected and the ABS indicator comes on, but not the VSA indicator, there are cases when the indicator stays on until the ignition switch is turned OFF, and cases when the indicator goes off automatically when the system returns to normal.
- DTC 61 or 62:
  The ABS and VSA indicators go off automatically when the system returns to normal.
- DTC 11, 13, 15, 17, 22, 31, 32, 33, 34, 35, 36, 37, 38, 45, 46, 47, 48, 54, 61, 62, 65, 66, 67, 68, 72, 73, 74,
  75, 76, 81, 91, 92 or 97:
  The ABS and VSA indicators stay on until the ignition switch is turned OFF whether or not the system returns to normal.
- DTC 12, 14, 16, 18, 51, 52 or 53:
  The ABS and VSA indicators stay on until the system returns to normal after the vehicle is driven.

Diagnostic Trouble Code (DTC)

The memory can hold 10 DTCs. However, when the same DTC is detected more than once, the more recent DTC is written over the earlier one. Therefore, when the same problem is detected repeatedly, it is memorized as a single DTC.
The DTCs are indicated in the order they occur.
The DTCs are memorized in the EEPROM. Therefore, the memorized DTCs cannot be canceled by disconnecting the battery. Do the specified procedures to clear the DTCs.

Self-diagnosis

Self-diagnosis can be classified into two categories:
- Initial diagnosis: Done right after the ignition switch is turned ON (II) and until the ABS or VSA indicators go off.
- Regular diagnosis: Done right after the initial diagnosis until the ignition switch is turned OFF.
When the system detects a problem, the VSA control unit shifts to fail-safe mode.

Kickback

The pump motor operates when the ABS or VSA is functioning, and the fluid in the reservoir is forced out to the master cylinder, causing kickback at the brake pedal.

Pump Motor

The pump motor operates when the ABS/TCS or VSA is functioning.
The VSA control unit checks the pump motor operating during regular diagnosis when the vehicle is driven over 15 km/h (10 mph) the first time after the ignition switch is turned ON (II). You may hear the motor operate at this time, but it is normal.

Brake Fluid Replacement/Air Bleeding

Brake fluid replacement and air bleeding procedures are identical to the procedures used on vehicles not equipped with VSA.

How to Troubleshoot DTCs

The troubleshooting flowchart procedures assume that the cause of the problem is still present and the ABS and/or VSA indicator is still on. Following the flowchart when the ABS and/or VSA indicator does not come on can result in incorrect diagnosis.
The connector illustrations show the female terminal connectors with a single outline and the male terminal connectors with a double outline.

1. Question the customer about the conditions when the problem occured, and try to reproduce the same conditions for troubleshooting. Find out when the ABS and/or VSA indicator came on, such as during ABS control, after ABS control, when vehicle was travelling at a certain speed, etc.

2. When the ABS or VSA indicator does not come on during the test drive, but troubleshooting is done based on the DTC, check for loose connectors, poor contact of the terminals, etc. before you start troubleshooting.

3. After troubleshooting, or repairs are done, clear the DTCs, and test-drive the vehicle under the same conditions as originally set with the DTCs. Make sure the ABS and VSA indicators do not come on.

How to Retrieve DTCs

1. With the ignition switch OFF, connect the HDS to the 16P data link connector (DLC) (A) under the driver's side of the dashboard.

2. Turn the ignition switch ON (II), and follow the prompts on the HDS to display the DTC(s) on the screen. After determining the DTC, refer to the DTC Troubleshooting.

NOTE: See the HDS Help menu for specific instructions.

How to Clear DTCs

1. With the ignition switch OFF, connect the HDS to the 16P data link connector (DLC) (A) under the driver's side of the dashboard.

2. Turn the ignition switch ON (II), and clear the DTC(s) by following the screen prompts on the HDS.

NOTE: See the HDS Help menu for specific instructions.