When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I want to measure the amount of voltage my fuel pump (Supra tt pump) is receiving.
But before removing all the stuff out the trunk I noticed the power fc has a fuel voltage number. Is this the number I am looking for or do I need to setup a multimeter to find the correct number? If I need to go the multimeter route do I simply find the red wire in the connector and the ground ? Can anyone please walk me through how to check the voltage with the multi meter?
here is a pic of the power fc sensor check I am asking about
that's the reading for the fuel temp sensor as i recall, the PFC doesn't monitor fuel pump voltage at all. that is highlighted because it is not receiving a pull down from the 5 volt ref and is normal if you have omitted that sensor. (it's not a critical sensor anyways, even in the slightest)
the color of the wire should be black/yellow at the pump inside the service cavity in the trunk if memory serves, wiring diagrams are wrong because they show the wiring color of the pump once it has transitioned inside the tank. if you pull the pump module you'll see the referenced blue wire, inside the cockpit you'll see the black/yellow heavy gauge wire up to the bulkhead.
Last edited by notanymore; Sep 30, 2025 at 09:05 PM.
that's the reading for the fuel temp sensor as i recall, the PFC doesn't monitor fuel pump voltage at all. that is highlighted because it is not receiving a pull down from the 5 volt ref and is normal if you have omitted that sensor. (it's not a critical sensor anyways, even in the slightest)
the color of the wire should be black/yellow at the pump inside the service cavity in the trunk if memory serves, wiring diagrams are wrong because they show the wiring color of the pump once it has transitioned inside the tank. if you pull the pump module you'll see the referenced blue wire, inside the cockpit you'll see the black/yellow heavy gauge wire up to the bulkhead.
good info thanks.
and yes that makes sense as the temp sensor has been deleted
the fuel pump wire may be black/white, mazda alternated with black and white and black and yellow for engine control accessory power over the years so i don't recall which was used on the FD right now since i don't have one in front of me.
