ECU Power Feeds

The ECU receives its ignition-switched power from the EFI main relay on all of Toyota's EFI systems. In addition to the ignition +B power feed, all P7 and TCCS ECUs have a direct battery feed, identified as BATT, supplied from either the EFI, STOP, or ECU +B fuse. The EFI main relay +B output is the power source which feeds the ECU and related engine control circuits. The direct battery feed (terminal BATT) serves to maintain voltage to the ECU keep alive memory when the ignition switch is off. Conventional EFI has no keep alive memory capabilities and, therefore, uses only an ignition switched power feed from the EFI main relay.

DIY Battery Repair

DIY Battery Repair

You can now recondition your old batteries at home and bring them back to 100 percent of their working condition. This guide will enable you to revive All NiCd batteries regardless of brand and battery volt. It will give you the required information on how to re-energize and revive your NiCd batteries through the RVD process, charging method and charging guidelines.

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