Initial Inspection and Diagnostic Overview

ABS Indicator
1. If the system is OK, the ASS indicator comes on for two seconds (initial turn on) after turning the ignition switch ON (II), then the ASS indicator goes off. After that time, the ASS indicator comes on again after starting the engine, then the ABS indicator goes off two seconds after the ignition switch return to ON (II). This occurs because the ABS control unit activates by the power source circuit that is connected only when the ignition switch is ON (II).
2. If a problem occurs, the Central Processing Unit (CPU) diagnoses the problem area and the problem condition, then the CPU memorizes the Diagnostic Trouble Code (DTC) and turns on the ABS indicator. If the system is OK, the ASS indicator does not come on except when the ignition switch is initially turned on.
3. If the problem is detected intermittently or continuously, the ABS indicator indication pattern is different as described below.
- DTC 61 or 62:
The ABS indicator comes on when a problem is detected in every time the system is activated, and the ABS indicator goes off when the system returns to normal.
- DTC 11, 13, 15, 17, 31, 32, 33, 34, 35, 36, 37, 38, 54, 71 or 81:
The ABS indicator comes on when a problem is detected in every time the system is activated, and the ABS indicator continues on until the ignition switch is turned OFF regardless of the system returns to normal or not.
- DTC 12, 14, 16, 18, 21, 22, 23, 24, 41, 42, 43, 44, 51, 52 or 53:
The ABS indicator comes on when a problem is detected, and the ABS indicator continues on until the ignition switch is turned OFF. The ABS indicator goes off when the system is activated the next time.
4. The ABS indicator comes on when the ABS control unit detects a problem in the system. However, even though the system is operating properly, the ASS indicator will come on, under the following conditions. To determine the actual cause of problem, question the customer about the problem, taking these conditions into consideration.
- Only drive wheel (or wheels) rotate
- One drive wheel is stuck
- Vehicle spin
- ASS continuous operate for a long time
- Signal disturbance

Diagnostic Trouble Code (DTC)
1. If a problem occurs in the system, the Central Processing Unit (CPU) diagnoses the problem area and the problem condition, then the CPU memorizes the Diagnostic Trouble Code (DTC) into the EEPROM (non-volatile memory).
2. The DTC clearing is possible only when performing the specified procedures, and the DTC is not cleared under the following conditions.
- Turning the ignition switch off or disconnecting the battery terminal
- The system returns to normal
3. The memory can hold any number of DTCs. However, when the same DTC is detected more than once, the later one is written over the previous one. Therefore, when the same problem is detected repeatedly, it is memorized as one DTC.
4. The DTCs are indicated in the order of ascending number, not in the order they occur.
5. Perform the specified procedures to indicate the DTCs.

Self-diagnosis
1. Self-diagnosis can be classified into two categories.
- Initial diagnosis: Performed right after the engine starts and until the ASS indicator goes off.
- Regular diagnosis: Performed right after the initial diagnosis and until the ignition switch is turned off.
2. When a problem is detected by self-diagnosis, the system
- Turns the ASS indicator ON
- Memorizes the DTC
- Stops ASS control

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

Pump Motor
1. The pump motor operates when the ABS is functioning.
2. The ABS control unit checks the pump motor operation during initial diagnosis when the vehicle is started. You may hear the motor operate at this time, but it is normal.

Brake Fluid Replacement/Air Bleeding
1. Brake fluid replacement and air bleeding procedures are the same as vehicles without ABS. To ease bleeding, start with the front wheels.

Troubleshooting
1. The troubleshooting flowcharts procedures assume that the cause of the problem is still present and the ABS indicator is still on. Following the flowchart when the ABS indicator does not come on can result in incorrect diagnosis.
2. Question the customer about the conditions when the problem occurred, and try to reproduce the same conditions for troubleshooting. Find out when the ABS indicator came on, such as during initial diagnosis, during ABS control, after ABS control, when vehicle speed was at a certain speed, etc.
3. When the ABS indicator does not come on during the test-drive, but troubleshooting is performed based on the DTC, check for loose connectors, poor contact at the terminals, etc. before you start troubleshooting.
4. After troubleshooting, erase the DTC and test-drive the vehicle. Be sure the ABS indicator does not come on.
5. The connector illustrations show the female terminals with a single outline and the male terminals with a double outline.

ABS Function Test
To simulate ABS operation and activate the solenoid valves and pump, use the Honda PGM Tester.
Connect the PGM Tester to the 16P Data Link Connector (DLC). When the System Select menu is displayed, select the ABS Test Mode menu and follow the tester's prompts.