Toyota Sienna Service Manual: Vehicle Speed Signal Circuit between Radio and Navigation Assembly and Combination Meter
DESCRIPTION The radio and navigation assembly receives a vehicle speed signal from the combination meter and information about the GPS antenna, and then adjusts vehicle position.
HINT:
- A voltage of 12 V or 5 V is output from each ECU and then input to the combination meter. The signal is changed to a pulse signal at the transistor in the combination meter. Each ECU controls the respective system based on the pulse signal.
- If a short occurs in an ECU, all systems in the diagram below will not operate normally.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 CHECK OPERATION OF SPEEDOMETER
- Drive the vehicle and check if the function of the speedometer on the combination meter is normal.
OK: Actual vehicle speed and the speed indicated on the speedometer are the same
HINT: The vehicle speed sensor is functioning normally when the indication on the speedometer is normal.
2 INSPECT RADIO AND NAVIGATION ASSEMBLY
- Disconnect the radio and navigation assembly connector R12.
- Measure the voltage.
- Jack up either one of the drive wheels.
- Move the shift lever to the neutral position.
- Turn the ignition switch to the ON position
- Measure the voltage between terminal SPD of the radio and navigation assembly and body ground when the drive wheels are turned slowly.
OK: Voltage pulses as shown in the illustration.
3 CHECK HARNESS AND CONNECTOR (COMBINATION METER - RADIO AND NAVIGATION ASSEMBLY)
- Disconnect the radio and navigation assembly connector R12 and combination meter connector C10.
- Measure the resistance according to the value(s) in the table below.
Standard resistance
4 CHECK HARNESS AND CONNECTOR (COMBINATION METER - RADIO AND NAVIGATION ASSEMBLY)
- Disconnect the radio and navigation assembly connector R12 and combination meter connector C10.
- Measure the resistance according to the value(s) in the table below.
Standard resistance
HINT: If the resistance between terminal SPD and body ground is less than 10 kΩ, there may be a short in a wire harness, connector, or an ECU.
REPLACE COMBINATION METER
Black Screen
INSPECTION PROCEDURE
1 CHECK DISPLAY SETTING
Check that the display is not in "Screen OFF" mode.
OK:
The display setting is not in "Screen OFF" mode.
2 CHECK IMAGE QUALIT ...
Steering Pad Switch Circuit
DESCRIPTION
This circuit sends an operation signal from the steering pad switch to the
radio receiver.
If there is an open in the circuit, the navigation system cannot be operated
using the st ...
Other materials:
Mass or Volume Air Flow Circuit Range / Performance Problem
DESCRIPTION
Refer to DTC P0100 (See page ES-116).
MONITOR DESCRIPTION
The MAF meter is a sensor that measures the amount of air flowing through the
throttle valve. The ECM
uses this information to determine the fuel injection time and to provide an
appropriate air-fuel ratio.
Insi ...
Brake
GENERAL MAINTENANCE
1. INSPECT BRAKE LINE PIPES AND HOSES
HINT:
Check the entire circumference and length of the brake
hoses using a mirror as required in a well-lighted area.
Turn the front wheels fully right or left before checking
the front brakes.
(a) Check all the brake lines and h ...
Shift Solenoid "E" Performance (Shift Solenoid
Valve SR)
SYSTEM DESCRIPTION
The ECM uses signals from the vehicle speed sensor to detect the actual gear
position (1st, 2nd, 3rd, 4th
or 5th gear).
Then the ECM compares the actual gear with the shift schedule in the ECM memory
to detect mechanical
problems of the shift solenoid valves, valve b ...
