TOYOTA PRIUS 2001 Service Repair Manual

I1907632 1COOL
WARM
DI±904
± DIAGNOSTICSAIR CONDITIONING SYSTEM
2001 PRIUS (RM778U)
2 Check air mix damper position sensor.
PREPARATION:
Remove air mix control servomotor (See page AC±56).
CHECK:
Measure resistance between terminals 1 and 2 of air mix control
servomotor connector.
OK:
Resistance : 4.2 ± 7.8 kW
CHECK:
While operating air mix control servomotor as shown in the pro-
cedure on page DI±906, measure resistance between termi-
nals 2 and 3 of air mix control servomotor connector.
OK:
PositionResistance
Max. COOL3.6 ± 6.7 kW
Max. WARM0.6 ± 1.1 kW
HINT:
As the air mix control servomotor moves from cool side to hot
side, the resistance decreases gradually without interruption.
NG Replace air mix control servomotor.
OK
3 Check harness and connector between A/C amplifier and air mix control servo-
motor (See page IN±41).
NG Repair or replace harness or connector.
OK
Check and replace A/C amplifier.

4
1
0
100%Damper opening angle4.1 V
0.9 V
TPI terminal voltage (V)
I14169
A/C Control Assembly A14
Air Inlet Control
Servomotor
A9
S5TPI 19
SGTPI A9
2 118
18TPI
A9 W
3
W
W
± DIAGNOSTICSAIR CONDITIONING SYSTEM
DI±905
2001 PRIUS (RM778U)
DTC 32, 42 Air Inlet Damper Position Sensor Circuit
CIRCUIT DESCRIPTION
This sensor detects the position of the air inlet damper and
sends the appropriate signals to the A/C amplifier. The position
sensor is built into the air inlet control servomotor.
DTC No.Detection ItemTrouble Area
32Short to ground or power source circuit in air inlet damper posi-
Air inlet damperposition sensor32Short to ground or ower source circuit in air inlet dam er osi
tion sensor circuit.

Air inlet damper position sensor

Harness or connector between air inlet control servomotor
42Air inlet damper position sensor value does not change even if
A/C amplifier operates air inlet control servomotor.
Harness or connector between air inlet control servomotor
and A/C amplifier

A/C amplifier
WIRING DIAGRAM
DI7SD±01

I18164
SGTPI
TPION
(±) (+)
DI±906
± DIAGNOSTICSAIR CONDITIONING SYSTEM
2001 PRIUS (RM778U)
INSPECTION PROCEDURE
1 Check voltage between terminals TPI and SGTPI of A/C amplifier connector.
PREPARATION:
(a) Remove center cluster module control with connectors
still connected.
(b) Turn ignition switch ON.
CHECK:
Press REC/FRS switch to change air inlet between fresh and
recirculation air and measure voltage between terminals TPI
and SGTPI of A/C amplifier when the air inlet servomotor oper-
ates.
OK:
REC/FRS SwitchVoltage
REC3.5 ± 4.5 V
FRS0.5 ± 1.8 V
HINT:
As the air inlet control servomotor is moved from REC side to
FRS side, the voltage decreases gradually without interruption.
NG Go to step 2.
OK
Proceed to next circuit inspection shown on problem symptoms table (See page DI±874). Howev-
er, if DTC 32 or 42 is displayed, check and replace A/C amplifier.

I1907732 1
REC
FRS
± DIAGNOSTICSAIR CONDITIONING SYSTEM
DI±907
2001 PRIUS (RM778U)
2 Check air inlet damper position sensor.
PREPARATION:
Remove air inlet control servomotor (See page AC±33).
CHECK:
Measure resistance between terminals 1 and 2 of air inlet con-
trol servomotor connector.
OK:
Resistance : 4.2 ± 7.8 kW
CHECK:
While operating air inlet control servomotor as in the procedure
on page DI±909, measure resistance between terminals 2 and
3 of air inlet control servomotor connector.
OK:
Resistance :
Damper PositionResistance
REC side3.4 ± 6.2 kW
FRS side0.8 ± 1.6 kW
HINT:
As the air inlet control servomotor is moved from REC side to
FRS side, the resistance decreases gradually without interrup-
tion.
NG Replace air inlet control servomotor.
OK
3 Check harness and connector between A/C amplifier and air inlet control servo-
motor (See page IN±41).
NG Repair or replace harness or connector.
OK
Check and replace A/C amplifier.

TPM terminal voltage
(V)
4.3
0.7
0 100 %
Damper opening angle
I18402
A/C Amplifier A16
Air Outlet Control Servomotor
A9S5TPM
8SGTPM A9
31
9 7
TPM A9 W 5
II1
3
II1
4
II1W
W W
BR±W2
GR±L DI±908
± DIAGNOSTICSAIR CONDITIONING SYSTEM
2001 PRIUS (RM778U)
DTC 33, 43 Air Outlet Damper Position Sensor Circuit
CIRCUIT DESCRIPTION
This sensor detects the position of the air outlet damper and
sends the appropriate signals to the A/C amplifier.
The position sensor is built into the air outlet damper control ser-
vomotor assembly.
DTC No.Detection ItemTrouble Area
33Short to ground or power source circuit in air outlet damper
position sensor circuit.
Air outlet damper position sensor.

Harness or connector between air outlet damper control ser-
43Air outlet damper position sensor value does not change even
if A/C amplifier operates air outlet damper control servomotor.

Harness or connector between air outlet dam er control ser-
vomotor assembly and A/C amplifier.

A/C amplifier.
WIRING DIAGRAM
DI7SE±01

I18166
ON
(+) (±)SGTPM
TPM
± DIAGNOSTICSAIR CONDITIONING SYSTEM
DI±909
2001 PRIUS (RM778U)
1 Check voltage between terminals TPM and SGTPM of A/C amplifier connector.
PREPARATION:
(a) Remove center cluster module control with connectors
still connected.
(b) Turn ignition switch ON.
CHECK:
Measure the voltage between terminals TPM and SGTPM of
A/C amplifier.
OK:
Air inlet selectorVoltage
FACE3.5 ± 4.5 V
DEF0.5 ± 1.5 V
HINT:
As the air outlet damper control servomotor is moved from
FACE side to DEF side, the voltage decreases gradually with-
out interruption.
NG Go to step 2.
OK
Proceed to next circuit inspection shown on problem symptoms table (See page DI±874). Howev-
er, if DTC 34 or 44 is displayed, check and replace A/C amplifier.

I19078
DEF
FACE
1
2
3
DI±910
± DIAGNOSTICSAIR CONDITIONING SYSTEM
2001 PRIUS (RM778U)
2 Check air outlet damper position sensor.
PREPARATION:
Remove air outlet servomotor (See page AC±57).
CHECK:
Measure resistance between terminals 1 and 2 of air outlet ser-
vomotor assembly connector.
OK:
Resistance : 4.2 ± 7.8 kW
CHECK:
While operating air outlet damper control servomotor as in the
procedure on page DI±912, measure resistance between ter-
minals 2 and 3 of air outlet damper control servomotor.
OK:
Resistance:
Damper PositionResistance
DEF3.6 ± 6.7 kW
FACE0.6 ± 1.1 kW
HINT:
As the air outlet servomotor moves from DEF side to FACE side,
the resistance decreases gradually without interruption.
NG Replace air outlet control servomotor assem-
bly.
OK
3 Check harness and connector between A/C amplifier and air outlet control servo-
motor assembly (See page IN±41).
NG Repair or replace harness or connector.
OK
Check and replace A/C amplifier.

I18391
A/C Amplifier
AMC A914
W II19
AMH A913
IG A71
GND A77 L
F18
FL Block No. 2
BatteryA15
Air Mix Control
Servomotor
Instrument Panel J/B
I15
Ignition
SW 4
BR±R
J20
J/C
C 5
W II1 10
C
R R 2D3
2H1
2D6
2K8
2B3
8
2D HTR
IG1 Relay
AM1B±Y
J/C 35
214
W±GIG1
AM1
2 W
W±B J25A
J24A
W±B
A
J11
J/C
ID MAINFL Block No. 1
F111
F131
1
DC/DC
± DIAGNOSTICSAIR CONDITIONING SYSTEM
DI±911
2001 PRIUS (RM778U)
DTC 41 Air Mix Control Servomotor Circuit
CIRCUIT DESCRIPTION
This air mix control servomotor is controlled by the A/C amplifier and moves the air mix damper to the desired
position.
DTC No.Detection ItemTrouble Area

Air mix control servomotor.
41Air mix damper position sensor value does not change even if
Air mix control servomotor.

Air mix damper position sensor.
H t b t A/C lifi d i i41Air mix dam er osition sensor value does not change even if
A/C amplifier operates air mix control servomotor.
Harness or connector between A/C amplifier and air mix con-
trol servomotor, air mix damperposition sensor.trol servomotor, air mix damper position sensor.

A/C amplifier.
WIRING DIAGRAM
DI7SF±01

Max. COOL e 20.5 (66)
21.0 e 23.5 (67 e72)±10 % (Fully closed)Cool air comes out Temp. Setting °C (°F)Air Mix Damper
Condition
24.0 e 26.0 (73 e77)
26.5 e 29.0 (78 e83)
29.5 (84) eMax. WARM100 % (Fully opened)
""
50 %
"
Warm air comes out
DI±912
± DIAGNOSTICSAIR CONDITIONING SYSTEM
2001 PRIUS (RM778U)
INSPECTION PROCEDURE
1 Actuator check.
PREPARATION:
(a) Warm up the engine.
(b) Set to the actuator check mode (See page DI±866).
CHECK:
Operate the temperatur control switch and check the operation of the air mix damper and the condition of
the blower.
OK:
OK Proceed to next circuit inspection shown on
problem symptoms table (See page DI±874).
NG

I19079
To COOL54
(±)
(+)
I19080
54
(±)
(+)
To WARM
± DIAGNOSTICSAIR CONDITIONING SYSTEM
DI±913
2001 PRIUS (RM778U)
2 Check air mix control servomotor.
PREPARATION:
Remove air mix control servomotor (See page AC±56).
CHECK:
Connect positive (+) lead to terminal 4 and the negative (±) lead
to terminal 5.
OK:
The lever turns smoothly to COOL side.
CHECK:
Connect negative (±) lead to terminal 4 and positive (+) lead to
terminal 5.
OK:
The lever turns smoothly to WARM side.
NG Replace air mix control servomotor.
OK
3 Check harness and connector between A/C amplifier and air mix control servo-
motor (See page IN±41).
NG Repair or replace harness or connector.
OK
Check and replace A/C amplifier.