Honda 2004 Odyssey Service Manual page 1242

General Troubleshooting Information
ABS Indicator
• If the system is OK, the ABS indicator goes off
2 seconds after turning the ignition switch ON (II)
without starting the engine, and then comes on again
and goes off 2 seconds later after starting the engine.
This occurs because the ABS control unit is turned on
by the IG2 power source.
• The ABS indicator comes on when the ABS control
unit detects a problem in the system.
To determine the actual cause of the problem, question
the customer about the problem, taking the above-
listed conditions into consideration.
• When a problem is detected and the ABS indicator
comes on, 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. For ABS DTCs 61 and 62,
the indicator goes off automatically when the system
returns to normal. For all other codes, the indicator
stays on until the ignition switch is turned OFF.
• For ABS DTCs 12, 14, 16, 18, 21, 22, 23, 24, 51, 52 and
53, the ABS indicator goes off when the vehicle is
driven again and the system is OK after the ignition
switch is turned from OFF to ON (II). However, if the
DTC is cleared, the CPU resets, and the indicator goes
off right after the engine is started if the system is OK.
Diagnostic Trouble Code (DTC)
• If the CPU cannot be activated, or it fails, the ABS
indicator comes on, but the DTC is not memorized.
• The memory can hold any number of 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 ascending number order,
not in the order that they occur.
• The DTCs are memorized in the EEPROM (non-
volatile memory). 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 engine starts and until the ABS
indicator goes off.
– Regular diagnosis:
Done right after the initial diagnosis until the
ignition switch is turned OFF.
• When a problem is detected by self-diagnosis, the
system shifts to fail-safe mode (see step 1 on page
19-52).
Kickback
The pump 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
• The pump motor operates when the ABS is
functioning.
• 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.
(cont'd)
19-41