Toyota Sienna Service Manual: Active Control Engine Mount System
DESCRIPTION
LOCATION
The Active Control Engine Mount (ACM) system decreases engine vibration at
engine idling using the
ACM VSV. The VSV is controlled by a pulse signal transmitted to the VSV from the
ECM. The frequency
of this pulse signal is matched to the engine speed to decrease engine
vibration.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 CHECK VACUUM HOSES
- If the hose is damaged, replace the vacuum hose
assembly.
- Check the air and vacuum hoses for looseness,
disconnection and blockage.
2 CHECK VACUUM
- Start the engine.
- Disconnect the vacuum hose from the air cleaner cap.
- Check that the disconnected port located on the vacuum
tank applies suction to your finger.
OK:
Vacuum pressure exists.
- Reconnect the vacuum hose.
3 INSPECT ECM
- Connect the oscilloscope between terminals ACM and
E1 of the E9 and E11 ECM connectors.
- Warm up the engine to normal operating temperature.
- Turn the A/C switch on.
- Measure the voltage according to the value(s) in the
table below.
Standard voltage
4 INSPECT DUTY VACUUM SWITCHING VALVE (RESISTANCE)
- Disconnect the V3 VSV for ACM connector.
- Measure the resistance according to the value(s) in the
table below.
Standard resistance:
19 to 21 Ω at 20C (68F)
- Reconnect the VSV for ACM connector.
5 CHECK HARNESS AND CONNECTOR (VSV FOR ACM - ECM)
- Check the wire harness between the VSV for ACM
connector and the ECM connector.
- Disconnect the V3 VSV for ACM connector.
- Disconnect the E9 ECM connector.
- Measure the resistance according to the value(s) in
the table below.
Standard resistance:
Check for open
Check for open
- Reconnect the ECM connector.
6 INSPECT FUSE (EFI NO. 2 FUSE)
- Remove the EFI No. 2 fuse from the engine room
junction block.
- Measure the resistance according to the value(s) in the
table below.
Standard resistance:
Below 1 Ω
- Reinstall the EFI No. 2 fuse.
7 INSPECT RELAY (EFI RELAY)
- Remove the EFI relay from the engine room junction
block.
- Measure the resistance according to the value(s) in the
table below.
Standard resistance
- Reinstall the EFI relay.
8 CHECK HARNESS AND CONNECTOR (VSV FOR ACM - EFI RELAY)
- Check the wire harness between the VSV for ACM and
the EFI relay.
- Remove the EFI relay from the engine room junction
block.
- Measure the resistance according to the value(s) in
the table below.
Standard resistance:
Check for open
- Reconnect the VSV for ACM connector.
- Reinstall the EFI relay.
CHECK ECM POWER SOURCE CIRCUIT
9 INSPECT DUTY VACUUM SWITCHING VALVE (OPERATION)
- Remove the VSV for ACM.
- Check operation of the VSV for ACM when positive
battery voltage is applied to the terminals of the VSV for
ACM connector.
Positive battery voltage is not applied:
The air from pipe G is flowing out through pipes E
and H.
Positive battery voltage is applied:
The air from pipe F is flowing out through pipes E
and H.
- Reinstall the VSV for ACM.
10 INSPECT ENGINE MOUNTING INSULATOR ASSEMBLY FRONT
- Disconnect the vacuum hose from the front engine
mount insulator.
- Using a vacuum pump, apply vacuum of 80 kPa (600
mmHg, 25 in.Hg) and wait for 1 minute.
- Check that there is no change in the needle movement
of the vacuum pump gauge.
- Check that there is no fluid leakage caused by a break in
the diaphragm.
OK:
Vacuum pressure exists.
- Reconnect the vacuum hose.
SYSTEM OK
DTC P2A00 A/F Sensor Circuit Slow Response (Bank 1
Sensor 1)
DTC P2A03 A/F Sensor Circuit Slow Response (Bank 2
Sensor 1)
HINT:
DTC P2A00 indicates malfunctions related to the bank 1 A/F ...
RELATED DTCS
If any EVAP system DTCs are set, the malfunctioning area can be determined
using the table below.
NOTICE:
If the 0.02 inch reference pressure difference between the first and ...
Other materials:
How to proceed with
troubleshooting
HINT:
The intelligent tester can be used in steps 2, 3, 4, 6 and 9.
1 VEHICLE BROUGHT TO WORKSHOP
2 CONNECT INTELLIGENT TESTER TO DLC3
HINT:
If the display indicates a communication fault in the tester,
inspect the DLC3.
3 CHECK DTC AND FREEZE FRAME DATA
(a) Check for DTC(s) and freeze f ...
Mechanical system tests
1. PERFORM MECHANICAL SYSTEM TESTS
(a) Measure the stall speed.
The object of this test is to check the overall
performance of the transaxle and engine by
measuring the stall speeds in the D position.
NOTICE:
Driving test should be done on a paved road
(a nonskid road).
Per ...
Customize parameters
HINT:
The following items can be customized.
NOTICE:
After confirming whether the items requested by the
customer are applicable or not for customization,
perform the customize operation.
Be sure to record the current settings before
customizing.
When troubleshooting, make sure that ...