ECU Power Source Circuit
TIRE AND WHEEL: TIRE PRESSURE WARNING SYSTEM: ECU Power Source Circuit
- ECU Power Source Circuit
DESCRIPTION
This circuit supplies power to the tire pressure warning ECU and receiver. The power is also supplied to the tire pressure warning antenna via the ECU.
The tire pressure warning system is terminated when the system has a defect of this circuit. At this time, the tire pressure warning light on the combination meter assembly will come on.
WIRING DIAGRAM
INSPECTION PROCEDURE
PROCEDURE
1. INSPECT BATTERY
(a) Check the battery voltage.
Standard voltage:
11 to 14 V
NG -- REPLACE BATTERY
OK -- Continue to next step.
2. INSPECT FUSE (ECU-IG LH)
(a) Remove the ECU-IG LH fuse from the cowl side J/B.
(b) Check continuity of the ECU-IG fuse.
Standard:
Below 1 Ohms
NG -- REPLACE FUSE
OK -- Continue to next step.
3. INSPECT TIRE PRESSURE WARNING ECU AND RECEIVER
(a) Remove the tire pressure warning ECU and receiver with the connectors being connected.
(b) Turn the engine switch on (IG).
(c) Measure the voltage according to the value(s) in the table below.
Standard voltage:
NG -- CHECK HARNESS AND CONNECTOR (BATTERY - TIRE PRESSURE WARNING ECU AND RECEIVER)
OK -- PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Symptom Related Diagnostic Procedures
4. CHECK HARNESS AND CONNECTOR (BATTERY - TIRE PRESSURE WARNING ECU AND RECEIVER)
(a) Disconnect the tire pressure warning ECU and receiver J49 connector.
(b) Turn the engine switch on (IG).
(c) Measure the voltage according to the value(s) in the table below.
Standard voltage:
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
4. CHECK HARNESS AND CONNECTOR (TIRE PRESSURE WARNING ECU AND RECEIVER - BODY GROUND)
(a) Disconnect the tire pressure warning ECU and receiver J49 connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE TIRE PRESSURE WARNING ECU AND RECEIVER Removal