Troubleshooting Precautions; Abs Indicator; Diagnostic Trouble Code (Dtc); Self-Diagnosis - Honda CR-V 1997 Service Manual

Troubleshooting Precautions
ABS Indicator
1. If the system is OK, the ABS indicator goes off two seconds after turning the ignition switch ON
(II)
without starting
the engine. and then comes on again and goes off after two seconds. This occurs because the ASS control unit is
turned on
by
the IG2 power source.
2. Th e ASS 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 too, under the following conditions:
• Signal distu rbance
• Wheel spin
• Only drive wheels rotate
• Battery voltage fluctuates
To determine the actual cause of the problem, question the customer about the problem, taking these conditions into
consideration :
3. When a problem is detected and the ASS indicator comes on, the indicator ca n stay on until the ignition switch is
turned OFF, or it can automatically go off, depending on the mode.
• Indicator stays on until the ignition switch is turned off: When the system is in the system down mode.
• Indicator automatically goes off: When the system is in the control inhibition mode.
4. The ASS indicator stays on when the system is reactivated without erasing the OTC, but it goes off after starting the
vehi cle.
When the wheel sensor system is faulty and the ASS indicator comes on, the algorithm 01 the system automatically turns
off the ASS indicator after the wheel speed signal retums to the normal speed. Also, when the DTC is erased, the CPU is
reset and the ASS indicato r goes off when the system checked out normal by the initial diagnosis.
Th erefore , test-drive the vehicle after servicing the wheel sensor system, and be sure that the ABS indicator does not
come on.
5. When the ABS control unit outputs battery voltage to the gauge assembly, the ABS indicator goes off.
Diagnostic Trouble Code (DTC)
, . The diagnostic trouble code (DTC) is memorized when a problem is detected and the ASS indicator does not go off,
or when the ASS indicator comes on.
The OTC is not memorized when the ASS indicator comes on unless the CPU is activated.
2. The memory can hold any number of OTCs. However, when the same DTC is detected twice or more, the later one is
written over the old one.
The refore, when the same problem is detected repeatedly, it is recorded as one DTe.
3. The OTCs are indicated in the order of ascending number, not in the order they occur.
4. The DTCs are memorized in the EEPROM Inon-volatile memory).
Th erefore, the memorized DTCs ca nnot be ca nceled by disconnecting the battery. Perform the specified procedures to
erase the DTCs.
Self-diagnosis
1. Self-diagnosis can be classified into these four categories:
• Initial diagnosis: Performed right after the engine starts and until the ASS indicator goes off.
• Exce pt ASS control: Performed when the ASS is not functioning.
• During ASS control: Perform ed when the ASS is fun ctioning.
• During warning : Performed when the ASS indicator is ON .
2. Th e system performs the following control s when a problem is detected by the self-diagnosis:
• ASS indicator ON
• Memory of DTC
• Mode change to the "' system down mode" or th e "contro l inhibition mode" .
MODE ABS INDICATOR
MAIN SOLENOID
CPU
Restart condition DTC
RELAY VALVE
SYSTEM
ON
No Drive
Ignition
I
OFF - ON III)
Memory
DOWN operation inhibition
Operation· '
sWitch
CONTROL
ON
No Drive
Operation Automatic Memory
INHIBITION operation inhibition
'1: Except CPU failure
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