Circuit Description
WARNING: This page is about a different car, the 2002 Toyota Prius. However, it is still accessible from the selected car via links, so may be relevant.
Constant battery voltage is supplied to +BM terminal of ECM as the power source for the Electronic Throttle Control System (ETCS). DTC is set when battery voltage does not exist at +BM terminal of ECM. If DTC P1127 exists, ECM will turn off the power to throttle control motor and throttle valve is closed by the return spring. Possible causes are:
- Defective fuse.
- Power source for ETCS circuit is open or shorted.
- Defective ECM.