Vehicle Proximity Notification System (Diagnostics & Circuit Tests) (Base): Overview Toyota Prius Plug-in

SYSTEM DESCRIPTION

1. Vehicle Proximity Notification System When the vehicle is being driven quietly using the motor only, the vehicle proximity notification system outputs a warning sound from the vehicle approaching speaker assembly to inform pedestrians, cyclists etc., of the approach of the vehicle. The warning sound is output by the vehicle approaching speaker assembly at a volume level that will not be perceived as noise. Also the pitch of the sound changes in accordance with vehicle speed so that the sound reflects vehicle deceleration and acceleration. Vehicle proximity notification system operation automatically stops when the vehicle is stopped, the engine starts or the vehicle is driven at 20 km/h (12 mph) or more.

OPERATION CHECK

1. VEHICLE PROXIMITY NOTIFICATION SYSTEM OPERATION CHECK System operation check (vehicle stopped) Apply the parking brake. Turn the power switch on (IG). With the brake pedal depressed, confirm that the vehicle proximity notification system does not operate (produce a sound) when the shift state is changed from park (P) to neutral (N). When the brake pedal is released, confirm that the vehicle proximity notification system operates for approximately 3 seconds (produces a sound). System operation check (vehicle being driven) Turn the power switch on (READY). Operate the EV drive mode switch and drive the vehicle using EV drive mode. When the shift state is changed from park (P) to drive (D), confirm that the vehicle proximity notification system operates (produces a sound) when the vehicle is driven at speeds of 20 km/h (12 mph) or less using EV drive mode.

DESCRIPTION

The vehicle approaching speaker controller detects when the shift state is park (P). When the vehicle approaching speaker controller detects that the shift state has been changed to park (P) due to the operation of the transmission shift main switch (P position switch), it stops operating the vehicle approaching speaker.

Scheme 8

The vehicle approaching speaker controller detects brake operation by monitoring the signal from the stop light control ECU assembly. Vehicle approaching speaker operation is enabled when the vehicle approaching speaker controller receives a signal from the stop light control ECU assembly indicating that the brakes are not applied.

Scheme 9

The vehicle approaching speaker controller detects engine operation by monitoring the signal from the engine oil pressure switch assembly. Vehicle approaching speaker operation is disabled when the vehicle approaching speaker controller receives a signal from the engine oil pressure switch assembly indicating that the engine is operating.

Scheme 10

The vehicle approaching speaker controller causes the vehicle approaching speaker assembly to operate (produce a sound) when the vehicle is being driven using EV drive mode. When the vehicle is being driven in EV drive mode, the vehicle approaching speaker controller changes the tone of the sound in accordance with vehicle speed.

Scheme 11

Scheme 12

1. CHECK VEHICLE APPROACHING SPEAKER CONTROLLER (OUTPUT WAVEFORM) Check the output waveform. Disconnect the A69 vehicle approaching speaker assembly connector. Connect an oscilloscope to terminal A69-2 (+) and A69-1 (-). Check the signal waveform according to the condition(s) in the table below. Item Condition Tool setting 1 V/DIV., 200 ms./DIV. Vehicle condition Speaker operating* *: Use the operation check procedure to operate the speaker. Refer to «OPERATION CHECK»(ref-551655-S33481027342013051500000) . OK The waveform is displayed as shown in the illustration. TEXT IN ILLUSTRATION *a Front view of wire harness connector (to Vehicle Approaching Speaker Assembly) NG --> See step 2 OK --> See step 4
2. CHECK HARNESS AND CONNECTOR (VEHICLE APPROACHING SPEAKER CONTROLLER - VEHICLE APPROACHING SPEAKER ASSEMBLY) Disconnect the L140 vehicle approaching speaker controller connector. Disconnect the A69 vehicle approaching speaker assembly connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition L140-3 (SP+) - A69-2 (+) Always Below 1 ohms L140-8 (SP-) - A69-1 (-) Always Below 1 ohms L140-3 (SP+) - Body ground Always 10 kohms or higher L140-8 (SP-) - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> See step 3
3. PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to «PROBLEM SYMPTOMS TABLE»(ref-551655-S21008382472013051500000)
4. REPLACE VEHICLE APPROACHING SPEAKER ASSEMBLY. Refer to «REMOVAL»(ref-551635-S19821462742013051500000)

The vehicle approaching speaker controller receives the vehicle speed signal from the combination meter assembly.

HINT

1. A voltage of 12 V or 5 V is output from each ECU and then input to the combination meter assembly. The signal is changed to a pulse signal at the transistor in the combination meter assembly. Each ECU controls the respective system based on the pulse signal.
2. If a short occurs in any of the ECUs or in the wire harness connected to an ECU, all systems in the diagram below will not operate normally.

Scheme 13

Scheme 14

1. INSPECT COMBINATION METER ASSEMBLY (OUTPUT WAVEFORM) Check the input waveform. Remove the combination meter assembly with the connector(s) still connected. Connect an oscilloscope to terminal L27-7 (+S) and body ground. Turn the power switch on (IG). Turn the wheel slowly. Check the signal waveform according to the condition(s) in the table below. Item Condition Tool setting 5 V/DIV., 20 ms./DIV. Vehicle condition Wheel being rotated TEXT IN ILLUSTRATION *a Component with harness connected (Combination Meter Assembly) OK The waveform is displayed as shown in the illustration. HINT: When the system is functioning normally, one wheel revolution generates 4 pulses. As the vehicle speed increases, the width indicated by (A) in the illustration narrows. NG --> See step 4 OK: Go to next step
2. CHECK HARNESS AND CONNECTOR (VEHICLE APPROACHING SPEAKER CONTROLLER - COMBINATION METER ASSEMBLY) Disconnect the L140 vehicle approaching speaker controller connector. Disconnect the L27 combination meter assembly connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition L140-6 (SPD) - L27-7 (+S) Always Below 1 ohms NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> See step 3
3. PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to «PROBLEM SYMPTOMS TABLE»(ref-551655-S21008382472013051500000)
4. GO TO METER / GAUGE SYSTEM. Refer to «Speed Signal Circuit»(ref-551586-S19557789222013051500000)

The vehicle proximity notification system may not function when there is a problem with the power supply of the vehicle approaching speaker controller.

Scheme 15