Speed Signal Circuit

WIPER AND WASHER: WIPER AND WASHER SYSTEM: Speed Signal Circuit
- Speed Signal Circuit

DESCRIPTION

The windshield wiper relay assembly (auto wiper relay) receives a vehicle speed signal from the combination meter to control the automatic windshield wiper system.

A voltage of 12 V or 5 V is output from the combination meter assembly and then input to the skid control ECU.

A voltage of 12 V or 5 V is output from each ECU or relay 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.

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 COMBINATION METER SYSTEM

(a) The circuit that sends vehicle speed signals to this system are inspected in the meter system Speed Signal Circuit.

(b) During the inspection, if there is an instruction that indicates to go back to the inspections for each system, proceed to the step below.

NEXT -- Continue to next step.

2. CHECK HARNESS AND CONNECTOR (WIPER RELAY - COMBINATION METER)

(a) Disconnect the E11 windshield wiper relay assembly (auto wiper relay) connector and E20 combination meter connector.

(b) Measure the resistance according to the value(s) in the table below.

Standard resistance:

NG -- CHECK HARNESS AND CONNECTOR (WIPER RELAY - JUNCTION BLOCK NO. 4)

OK -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE Symptom Related Diagnostic Procedures

3. CHECK HARNESS AND CONNECTOR (WIPER RELAY - JUNCTION BLOCK NO. 4)

(a) Disconnect the 4J junction block No. 4 connector.

(b) Measure the resistance according to the value(s) in the table below.

Standard resistance:

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (WIPER RELAY - JUNCTION BLOCK NO. 4)

OK -- REPAIR OR REPLACE HARNESS OR CONNECTOR (JUNCTION BLOCK NO. 4)