Honda 2004 Odyssey Service Manual page 1253

ABS Components
System Description (cont'd)
Self-diagnosis
1. The ABS control unit is equipped with a main CPU and a sub-CPU. Each CPU checks the other for problems.
2. The CPUs check the circuit of the system.
3. Self-diagnosis can be classifield into 2 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.
4. When a problem is detected by self-diagnosis, the system shifts to fail-safe mode.
Self-diagnosis Table
Diagnostic
Trouble Code
(DTC)
11, 13, 15, 17 Wheel sensor (open/short to body ground/short
to power)
12, 14, 16, 18 Wheel sensor (electrical noise/intermittent
interruption)
21 24 Pulser
31 38 Solenoid (short to body ground/short to wire)
41 44 Wheel lock
51 Motor lock
52 Motor stuck OFF
53 Motor stuck ON
54 ABS fail-safe relay
61 Low ignition voltage
62 High ignition voltage
71 Different diameter tire
81 Central Processing Unit (CPU) diagnosis, and
ROM/RAM diagnosis
NOTE:
• At the DTCs with '' '' mark, there are cases that the ABS control unit shifts to fail-safe mode A1, L1 when the ABS
control unit detects more than one DTC and for different wheel.
• If the ABS control unit detects the DTCs which have different fail-safe mode individually, the control unit take
priority the large number mode.
19-52
Detection Item Detection Timing
Initial Regular
Diagnosis Diagnosis
Fail-safe Mode
A2
A2, A2 and L2
A2 and L2
S, A1
A2 and L2
A2 and L2
A2 and L2
A2 and L2
S
B1, B2
B1, B2
S
S, A1