DIAGNOSIS SYSTEM DESCRIPTION (a) The transponder key ECU assembly controls the engine immobiliser system. Engine immobiliser system data and Diagnostic Trouble Codes (DTCs) can be read through the vehicle Data Link Connector 3 (DLC3). CHECK DLC3 (a) Check the DLC3. Click here INSPECT BATTERY VOLTAGE (a) Measure the battery voltage. Standard voltage: 11 to 14 V If the voltage is below 11 V, recharge or replace the battery. |
Toyota Tundra Service Manual > Sfi System: ECM Power Source Circuit
DESCRIPTION When the ignition switch is turned to ON, the battery voltage is applied to the IGSW terminal of the ECM. The output signal from the MREL terminal of the ECM causes a current to flow to the coil, closing the contacts of the integration relay (EFI relay) and supplying power to terminals + ...
