Vehicle Speed Signal Circuit Between Radio Receiver and Combination Meter

AUDIO / VISUAL: AUDIO AND VISUAL SYSTEM: Vehicle Speed Signal Circuit between Radio Receiver and Combination Meter

Vehicle Speed Signal Circuit between Radio Receiver and Combination Meter

DESCRIPTION

Audio function:
The circuit is necessary for the ASL (Auto Sound Levelizer) built into the radio receiver assembly. Speed signals are received from the combination meter and used for the ASL. The ASL function automatically adjusts the sound data in order to enable to hear the clear audio sound even when vehicle noise increases (as vehicle noise increases, the volume is turned up etc.).
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 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 METER / GAUGE SYSTEM
(a) The circuits that send vehicle speed signals to this system are inspected in the meter / gauge system Speed Signal Circuit.
(b) During inspection for the meter section, if there is an instruction that indicates to go back inspections for each system, proceed to the next step.
NEXT -- Continue to next step.
2. CHECK HARNESS AND CONNECTOR (COMBINATION METER - RADIO RECEIVER)




(a) Disconnect the radio receiver connector F8 and combination meter connector F2.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- CHECK HARNESS AND CONNECTOR (RADIO RECEIVER - NO. 3 JUNCTION BLOCK)
OK -- REPLACE RADIO RECEIVER
3. CHECK HARNESS AND CONNECTOR (RADIO RECEIVER - NO. 3 JUNCTION BLOCK)
(a) Disconnect the No. 3 junction block connector.
(b) Measure the resistance according to the value(s) in the table below.





Standard resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR OR EACH ECU (RADIO RECEIVER - NO. 3 JUNCTION BLOCK)
OK -- REPAIR OR REPLACE HARNESS OR CONNECTOR (NO. 3 JUNCTION BLOCK)