Discussion and questions related to the course EFI Wiring Fundamentals
After watching the fundamentals and practical course, as well as some other literature there is still a few things im not clear about when wiring hall effects sensors for engine position/timing.
I am using Hall effect sensors with rated voltage supply 4.5-24v
In the videos we are advised to wire the sensors to Power Supply and ground instead of Sensor Supply and ground, What is the reason for this?
Some people say that using the 5v Sensor supply can give a clearer signal, while others say that it unnecessarily loads the sensor supply circuit.
If i am to use the power supply and ground then where is the best place to source this? I cannot see any relevant pin on the ecu. As for the ground and shield do they really need to run back up the harness the way they just came to terminate on the engine block, or would it be acceptable to earth them to the chassis next to the ecu?
I havent seen the video but the hall sensor ground should definitely be connected to ECU sensor ground (or some ECUs have a specific trigger ground pin), and definitely not power or chassis ground.
For the power supply there is no advantage either way. All hall sensors I am familiar with only draw a few mA so arent going to load up the ECU 5V supply any more than any other sensor. If your particular sensor is rated at 4.5-24V then it has a built-in regulator so it is perfectly fine to connect to any other power source 8V, 12V, ecu or chassis, etc. I would generally use the ECU 5V if the sensor was compatible with 5V but you can use whatever is easiest in your case.