HYBRID/TROUBLE SHOOTING
3–111
CHECKLIST: P0A03 (TC79)
P0A03 (TC79)
Coolant temperature sensor High abnormality
Inspection Procedure
Step
Action
Description
Judgement
Check
(Yes/No)
Yes
No
1
Inspecting the
continuity of
PCU wire har-
ness (lower
side)
1. Set the starter key to the
"LOCK" position.
2. Disconnect the connectors of
coolant temperature sensor
and HV ECU1.
3. Using the electrical tester, mea-
sure the resistance between
the coolant temperature sen-
sor connector and the HV
ECU1 connector terminal.
<Measurement conditions>
Starter key: LOCK
<Tester connections>
Coolant temperature sensor con-
nector
–
HV ECU1 connector
1st terminal
–
30th terminal
2nd terminal
–
29th terminal
<Standard values>
Less than 1
The mea-
sured value is
within the
range of stan-
dard value: Go
to YES.
The mea-
sured value is
not within the
range of stan-
dard value: Go
to NO.
Go to step 2.
Replace the
PCU wire har-
ness (lower
side).
2
Inspecting the
coolant tem-
perature sen-
sor
1. Using the electrical tester, mea-
sure the resistance of coolant
temperature sensor.
<Measurement conditions>
Starter key: LOCK
<Tester connections>
Coolant temperature sensor con-
nector (sensor side)
1st terminal
–
2nd terminal
<Standard values>
0
C {32
F}: 5.3 k
–
6.2 k
20
C {68
F}: 2.3 k
–
2.6 k
30
C {86
F}: 1.5 k
–
1.8 k
The mea-
sured value is
within the
range of stan-
dard value: Go
to YES.
The mea-
sured value is
not within the
range of stan-
dard value: Go
to NO.
Go to step 3.
Replace the
coolant tem-
perature sen-
sor.
3
Inspecting the
signal line of
PCU wire har-
ness (lower
side) for short
circuit
1. Set the starter key to the
"LOCK" position.
2. For the 2nd terminal of coolant
temperature sensor connector,
inspect the signal line of PCU
wire harness (lower side) for
short circuit. (See "Inspecting
the PCU harness signal line for
short circuit.")
<Measurement conditions>
Starter key: LOCK
<Tester connections>
Coolant temperature sensor con-
nector
2nd terminal
–
Each signal line
<Standard values>
10 k
or more
Defect is
found: Go to
YES.
Defect is not
found: Go to
NO.
Replace the
PCU wire har-
ness (lower
side).
Go to step 4.