my daughter has a 2004 Toyota Highlander. the car wont start so i think it's the fuel pump since i can't hear it run. i took it out and checked the pump by directly hooking it up to my battery in the truck and it came on. i crossed the Horn relay and the EFI relay to see if it was a bad relay but still didn't make the pump come on. what else could there be to keep the pump from coming on?
My car has an automatic transmission.
Check the fuse. There could be more than one relay in the circuit, for example a circuit opening relay as well as an EFI relay. The fault could be due to high resistance in the circuit (even at the relay contacts) and so the only way to track down something like this is to power the circuit and check for voltage drop at EVERY segment of the circuit. Measuring segment by segment, you are either going to find an open or a voltage drop that is large enough that the pump won’t start. If you want these steps performed by a certified Mechanic, dispatched by YourMechanic right to your location, please request an electrical diagnostic and the responding certified mechanic will get this resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.
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