Vehicle Speed Signal Circuit

NAVIGATION: NAVIGATION SYSTEM (for HDD): Vehicle Speed Signal Circuit

Vehicle Speed Signal Circuit

DESCRIPTION

The display and navigation assembly performs switch operation control during driving by receiving a vehicle speed signal from the combination meter.
HINT:
- A voltage of 12 to 15 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 its respective system based on the pulse signal.
- 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.

WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK OPERATION OF SPEEDOMETER
(a) Drive the vehicle and check if the function of the speedometer in 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.

NG -- GO TO METER / GAUGE SYSTEM
OK -- Continue to next step.
2. CHECK HARNESS AND CONNECTOR (DISPLAY AND NAVIGATION ASSEMBLY - COMBINATION METER)




(a) Disconnect the L59 display connector.
(b) Disconnect the L10 meter connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE