EC-382
< COMPONENT DIAGNOSIS >
[VQ35HR]
P1551, P1552 BATTERY CURRENT SENSOR
P1551, P1552 BATTERY CURRENT SENSOR
Description
INFOID:0000000000956781
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:0000000000956782
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.
PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 8V with ignition
switch ON
>> GO TO 2.
2.
PERFORM DTC CONFIRMATION PROCEDURE
1.
Turn ignition switch ON and wait at least 10 seconds.
2.
Check 1st trip DTC.
Is 1st trip DTC detected?
YES
>> Go to
EC-383, "Diagnosis Procedure"
.
DTC No.
Trouble diagnosis name
DTC detecting condition
Possible cause
P1551
Battery current sensor circuit
low input
An excessively low voltage from the sen-
sor is sent to ECM.
• Harness or connectors
(Battery current sensor circuit is open
or shorted.)
[CKP sensor (POS) circuit is shorted.]
[CMP sensor (PHASE) (bank 2) circuit
is shorted.]
[EVT control position sensor (bank 2)
circuit is shorted.]
(APP sensor 2 circuit is shorted.)
(EVAP control system pressure sensor
circuit is shorted.)
(Refrigerant pressure sensor circuit is
shorted.)
• Battery current sensor
• Crankshaft position sensor (POS)
• Camshaft position sensor (PHASE)
(bank 2)
• Exhaust valve timing control position
sensor (bank 2)
• Accelerator pedal position sensor
• EVAP control system pressure sensor
• Refrigerant pressure sensor
P1552
Battery current sensor circuit
high input
An excessively high voltage from the sen-
sor is sent to ECM.