Toyota Sienna Service Manual: Clearance Warning ECU Power Source Circuit
DESCRIPTION
This circuit provides power to the clearance warning ECU.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 CHECK HARNESS AND CONNECTOR (CLEARANCE WARNING ECU - AIR CONDITIONER AMPLIFIER)
- Disconnect the connectors from the clearance warning ECU C9 and air conditioner amplifier connector A10 or A11.
- Measure the resistance according to the value(s) in the table below.
Standard resistance
2 CHECK HARNESS AND CONNECTOR (CLEARANCE WARNING ECU - BODY GROUND)
- Measure the resistance according to the value(s) in the table below.
Standard resistance
3 INSPECT CLEARANCE WARNING ECU
- Disconnect the clearance warning ECU connector.
- Turn the ignition switch ON.
- Turn the clearance sonar main switch ON.
- Measure the voltage between terminals +B and E of the ECU.
Standard voltage: 10 to 14 V
Result
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
4 INSPECT PRINTED WIRE INTEGRATION BOARD SUB-ASSEMBLY
- Check that the malfunction disappears when a known good printed wire integration board sub-assembly is installed.
OK: Malfunction disappears
REPLACE PRINTED WIRE INTEGRATION BOARD SUB-ASSEMBLY
5 INSPECT INTEGRATION PANEL SUB-ASSEMBLY
- Check that the malfunction disappears when a known good integration panel sub-assembly is installed.
OK: Malfunction disappears.
REPLACE INTEGRATION PANEL SUB-ASSEMBLY
No. 1 Clearance Warning Buzzer Circuit
DESCRIPTION
The clearance warning ECU receives the ultrasonic sensor signal to sound the
front warning buzzer.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 INSPECT FRONT BUZZER
Remove the c ...
No. 2 Clearance Warning Buzzer Circuit
DESCRIPTION
The clearance warning ECU receives the ultrasonic sensor signal to sound the
rear warning buzzer.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 CHECK HARNESS AND CONNECTOR (CLEARANCE WAR ...
Other materials:
Reassembly
1. INSTALL COOLER DRYER
(a) Using needle nose pliers, install the cooler dryer.
(b) Install a new O-ring on the cap.
(c) Sufficiently apply compressor oil to the fitting
surfaces of the O-ring and the cap.
Compressor oil:
ND-OIL 8 or equivalent
(d) Using a hexagon wrench 14 mm ( ...
Diagnostic trouble code chart
1. DTC CHECK
If a malfunction code is displayed during the DTC check ,
check the suspected area listed for that code in the table
below, and proceed to the appropriate page.
DIAGNOSTIC TROUBLE CODE CHART
DTC No.
Detection Item
Suspect Area
B1244
Light Se ...
Terminals of ECU
1. MULTIPLEX NETWORK GATEWAY ECU
Disconnect the G4 ECU connector.
Measure the voltage between the specified
terminals on the wire harness side connector.
If the result is not as specified, there may be a
malfunction on the wire harness side.
Measure the resistance between ...
