DTC C1257/57 IG Power Source: Wiring Diagram
- INSPECT BATTERY
- Check the battery voltage.
Standard voltage: 11 to 14 V
NG : RECHARGE OR REPLACE BATTERY
OK : Go To Next Step
- READ VALUE OF INTELLIGENT TESTER (IG VOLTAGE)
- Using the DATA LIST, check for proper functioning of the IG voltage.
Skid control ECU assembly
DATA REFERENCE CHARTItem Measurement Item/Range (Display) Normal Condition Diagnostic Note IG VOLTAGE ECU IG power voltage/ UNDER or NORMAL or OVER - - OK : Display is NORMAL
OK : REPLACE SKID CONTROL ECU ASSEMBLY
NG : Go To Next Step
- CHECK WIRE HARNESS (SKID CONTROL ECU ASSEMBLY - BATTERY AND BODY GROUND)
- Measure the voltage of the wire harness side connectors.
Standard voltage
TESTER CONNECTION AND SPECIFIED CONDITION CHARTTester Connection Condition Specified Condition A40-6 (IG1) - A40-17 (GND4) Ignition switch ON 10 to 14 V A40-6 (IG1) - A40-8 (GND3) Ignition switch ON 10 to 14 V A40-6 (IG1) - A39-6 (GND2) Ignition switch ON 10 to 14 V A40-6 (IG1) - A39-31 (GND1) Ignition switch ON 10 to 14 V A40-6 (IG1) - Body ground Ignition switch ON 10 to 14 V - Measure the resistance of the wire harness side connectors.
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Standard resistance
TESTER CONNECTION AND SPECIFIED CONDITION CHARTTester Connection Condition Specified Condition A40-17 (GND4) - Body ground Always Below 1 Ω A40-8 (GND3) - Body ground Always Below 1 Ω A39-6 (GND2) - Body ground Always Below 1 Ω A39-31 (GND1) - Body ground Always Below 1 Ω NG : REPAIR OR REPLACE HARNESS AND CONNECTOR
- Measure the voltage of the wire harness side connectors.
- INSPECT FUSE (ECU-IG1)
- Remove the ECU-IG1 fuse from the cowl side junction block LH.
- Measure the resistance of the fuse.
Standard resistance: Below 1 Ω
NG : REPLACE FUSE
OK : REPLACE SKID CONTROL ECU ASSEMBLY