2001 TOYOTA PRIUS Service Repair Manual

± AIR CONDITIONINGHEATER CONTROL ASSEMBLY
AC±81
2001 PRIUS (RM778U)
(c) Connect the positive (+) lead from the tester to terminal
10 and negative (±) lead to terminal 13 then check that the
voltage at each dial position, as shown in the chart below.
Dial positionSpecified condition
OFF "AUTO1.45 V
AUTO "LO2.25 V
LO "M13.05 V
M1 " M23.85 V
M2 " H14.65 V
If operation is not as specified, replace the cluster module cir-
cuit.

I15478
Hybrid Vehicle
Control ECU
C14
Cruise Control SW (Comb. SW)
A
W±B
5
LCCS 16
H14
CRUISE
CCS RES/
ACC
SET/
COAST
CANCEL
ECC
J17
J/C
IG A W±B
J18A
J194
± DIAGNOSTICSCRUISE CONTROL SYSTEM
DI±661
2001 PRIUS (RM778U)
Cruise Control Switch Circuit
CIRCUIT DESCRIPTION
This circuit carries the SET/COAST, RESUME/ACCEL and CANCEL signal (each voltage) to the ECU.
WIRING DIAGRAM
DI7NK±01

I19096
ON
CCS
(+) (±)
DI±662
± DIAGNOSTICSCRUISE CONTROL SYSTEM
2001 PRIUS (RM778U)
INSPECTION PROCEDURE
1 Check voltage between terminals CCS of hybrid vehicle control ECU connector
and body ground.
PREPARATION:
(a) Remove the hybrid vehicle control ECU with connector
still connected.
(b) Turn ignition switch ON.
CHECK:
Measure voltage between terminals CCS of hybrid vehicle con-
trol ECU connector and body ground, when each of the SET/
COAST, RESUME/ACCEL and CANCEL is turned ON.
Switch positionVoltage (V)
Neutral10 ±16 V
RES/ACC2.4 ± 3.8 V
SET/COAST4.7 ± 6.9 V
CANCEL6.9 ± 9.8 V
NG Proceed to next circuit inspection shown in
problem symptoms table (See page DI±648).
OK

I05156
RES/ACC
CANCEL
SET/COAST
4
3
I05126
CRUISE MAIN
Switch
43
± DIAGNOSTICSCRUISE CONTROL SYSTEM
DI±663
2001 PRIUS (RM778U)
2 Check control switch continuity.
PREPARATION:
(a) Remove steering wheel center pad.
(b) Disconnect the control switch connector.
CHECK:
Measure resistance between terminals 4 and 5 of control switch
connector when control switch is operated.
Switch positionResistance (W)
Neutral8 (No continuity)
RES/ACC220 ± 260
SET/COAST600 ± 660
CANCEL1,500 ± 1,600
NG Replace control switch.
OK
3 Check main switch continuity.
PREPARATION:
(a) Remove steering wheel center pad. (See page SR±6)
(b) Disconnect the control switch connector.
CHECK:
Check continuity between terminals 4 and 5 of control switch
connector when main switch is held ON and OFF.
OK:
Switch positionTester connectionSpecified condition
OFF±No continuity
Hold ON4 ± 5Continuity
NG Replace control switch.

DI±664
± DIAGNOSTICSCRUISE CONTROL SYSTEM
2001 PRIUS (RM778U)
OK
4 Check harness and connector between hybrid vehicle control ECU and cruise
control switch, cruise control switch and body ground
(See page IN±41).
NG Repair or replace harness or connector.
OK
Check and replace hybrid vehicle control
ECU (See page
IN±41).

± DIAGNOSTICSCOMBINATION METER SYSTEM
DI±679
2001 PRIUS (RM778U)
4. Fuel receiver gauge is inoperative or improper
INSPECTION PROCEDURE
1 Fuel gauge diagnosis check. (See page DI±669)
2 Reset inclination sensor. (See page BE±47)
3 Fuel sender gauge check. (See page BE±42)
NG Replace fuel tank.
OK
4 Multiplex communication circuit check. (See page DI±750)
CHECK:
Check if the communication between the combination meter and the multiplex communication circuit is nor-
mal or not.
No Multiplex communication circuit error.
Wire harness faulty.
Ye s
DI7XW±01