Visual inspection
Before diagnosing an ABS problem, fully ascertain whether or not the normal braking system is in working order. Many Common Brake Faults (dangling parking brake, leaking, etc.) affect the performance of the ABS. Visual inspection of certain components of the system can reveal the causes of external ABS malfunctions and identify a simple failure, thus reducing diagnostic time.
1. Check tire pressure; they must be approximately the same for the correct functioning of the system.
2. Check up level of a brake liquid in tanks.
3. Check lines, hoses, master cylinder assembly and brake calipers for leakage.
4. Visually inspect brake lines and hoses for excessive wear, thermal breakdown, punctures, contact with other parts, missing fasteners, snags, or deformation.
5. Check the calipers for rust or corrosion. Check for proper sliding, if required.
6. Check the calipers for the degree of freedom when pressing and releasing the brakes.
7. Inspect the wheel speed sensors for proper installation and fastening.
8. Inspect the speed sensor gears for broken teeth or looseness.
9. Inspect the wheels and tires on the car. They must be the same size and type in order to generate accurate speed signals.
10. Recheck the location of the damage. In some driver-driven situations, such as not releasing the parking brake fully, turning the wheel while accelerating, slipping due to excessive cornering speed, or driving on extremely rough roads, an error code is set and the alarm is activated. These "malfunctions" are not system breakdowns, but serve as examples of vehicle operation in conditions that disrupt the operation of the control unit.
11. Often the shutdown of the system occurs due to the loss of sensor signals to or from the control unit. The most common cause is not a faulty sensor, but a loose, corroded, or dirty connector. Check the harness and connector components carefully.
Warning Lamp Test
Once the warning light comes on, it stays on until the ignition is turned off and then on again or the code is cleared (if he is). The simplest system test is to simply turn on the ignition and check that the warning light is on. Start the engine; if the signal goes out after a few seconds, the system is working without errors. If the lamp does not go out, then further diagnostics in the workshop is required.
If the warning lamp does not come on when the ignition is turned on, then check the bulb, open circuit from fuse 13 on the Prelude or 1 on the Accord to the instrument cluster, open blue-red wire from the instrument cluster to the ABS control unit. There may also be no reliable connection between the control unit and the housing (open circuit "masses").
The lamp may remain on after starting the engine. Common causes - broken or weak connection of the ABS harness to the control unit, defective ABS fuse (2 on Accord or 27 on Prelude) or an open circuit in the white wire between the ABS fuses (2 or 27) and control unit. The fault can also be caused by an open circuit between fuses 17 (Prelude) or 8 (Accord) and safety relays, or open/short circuit in green/yellow wire to safety relays. Additionally, check for an open white-blue wire between the generator and the control unit. Also check for an open/short circuit in the blue-red wire from the measuring unit to the control unit.
The warning lamp lights up if the battery voltage drops below normal. After the voltage is restored, the system functions normally.
The ABS electronic control unit has self-diagnostic capabilities similar to the fuel injection system. If the electrical signal is outside the operating range, the control unit detects this condition and turns on the ABS warning lamp. The error code is stored in the system memory for subsequent identification.
Diagnosing the system requires the use of a Honda ABS tester. This is a sophisticated test tool available only from sales offices. In case the car warning light stays on during normal operation, carefully check the simple things. The most common causes of error or loss of signal are not the most difficult to find.
If the problem is not resolved by your efforts, have the vehicle inspected by your HONDA dealer.