Diagnosis and repair workflow
Work flow
Overall sequence

Detailed flow
1.Obtain information about symptom
Interview the customer to obtain as much information as possible about the conditions and environment under which the malfunction occurred.
>> GO TO 2.
2.Check symptom
>> Go to 3.
3.Check consult self-diagnosis results
Connect consult and perform self-diagnosis. Refer to mwi-26, "dtc index".
Are self-diagnosis results normal? Yes >> go to 4.
No >> go to 5.
4.Narrow down malfunctioning parts by symptom diagnosis
Perform symptom diagnosis and narrow down the malfunctioning parts.
>> Go to 5.
5.Repair or replace malfunctioning parts
Repair or replace malfunctioning parts.
Note:
If dtc is displayed, erase dtc after repairing or replacing malfunctioning parts.
>> Go to 6.
6.Final check
Check that the warning buzzer in the combination meter operates normally.
Does it operate normally? Yes >> inspection end.
No >> go to 1.
Wiring diagramIllumination control switch signal circuit
Diagnosis procedure
Regarding wiring diagram information, refer to mwi-28, "wiring diagram".
1.Check combination meter input signal
Turn ignition switch on.
Check voltage between the following terminals of the illumination
control switch.
Is the inspection result normal?
...
Diagnosis description : malfunction indicator lamp (MIL)
When emission-related ECU detects a malfunction in the emission
control systems components and/or the powertrain control components
(which affect vehicle emissions), it turns on/blinks MIL to
inform the driver that a malfunction has been detected.
The MIL illuminates when ignition switch is t ...
B142A Ignition voltage
Description
DTC B142A IGNITION VOLTAGE
Ignition voltage is supplied to the air bag diagnosis sensor unit when the
ignition is in the ON position. The air
bag diagnosis sensor unit will monitor for low or high ignition voltage.
PART LOCATION
Refer to SRC-5, "Component Parts Location" ...