P1554 BATTERY CURRENT SENSOR
EC-417
< COMPONENT DIAGNOSIS >
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P1554 BATTERY CURRENT SENSOR
Description
INFOID:0000000001911023
The power generation voltage variable control enables fuel consumption to be decreased by reducing the
engine load which is caused by the power generation of the generator. The battery current sensor is installed
to the battery cable at the negative terminal. The sensor measures the charging/discharging current of the bat-
tery. Based on the sensor signal, ECM judges whether or not the power generation voltage variable control is
performed. When performing the power generation voltage variable control, ECM calculates the target power
generation voltage based on the sensor signal. And ECM sends the calculated value as the power generation
command value to IPDM E/R. For the details of the power generation voltage variable control, refer to
CHG-8,
"System Description"
.
CAUTION:
Do not connect the electrical component or the ground wire directly to the battery terminal. The con-
nection causes the malfunction of the power generation voltage variable control, and then the battery
discharge may occur.
DTC Logic
INFOID:0000000001734239
DTC DETECTION LOGIC
NOTE:
If DTC P1554 is displayed with DTC P0643, first perform the trouble diagnosis for DTC P0643. Refer to
EC-
358, "DTC Logic"
.
DTC CONFIRMATION PROCEDURE
1.
PERFORM COMPONENT FUNCTION CHECK
Perform component function check. Refer to
EC-417, "Component Function Check"
.
NOTE:
Use component function check to check the overall function of the battery current sensor circuit. During this
check, a 1st trip DTC might not be confirmed.
Is the inspection result normal?
YES
>> INSPECTION END
NO
>> Go to
EC-418, "Diagnosis Procedure"
.
Component Function Check
INFOID:0000000001734240
1.
PRECONDITIONING
TESTING CONDITION:
• Before performing the following procedure, confirm that battery voltage is more than 12.8V at idle.
• Before performing the following procedure, confirm that all load switches and A/C switch are turned
OFF.
>> GO TO 2.
2.
PERFORM COMPONENT FUNCTION CHECK
With CONSULT-III
1.
Start engine and let it idle.
2.
Select “BAT CUR SEN” in “DATA MONITOR” mode with CONSULT-III.
3.
Check “BAT CUR SEN” indication for 10 seconds.
“BAT CUR SEN” should be above 2,300mV at least once.
Without CONSULT-III
1.
Start engine and let it idle.
DTC No.
Trouble diagnosis name
DTC detecting condition
Possible cause
P1554
Battery current sensor perfor-
mance
The output voltage of the battery current
sensor is lower than the specified value
while the battery voltage is high enough.
• Harness or connectors
(Battery current sensor circuit is open
or shorted.)
• Battery current sensor