- Fri Jan 17, 2025 7:10 pm
#70518
Hey all,
I’ve been finishing up a typical LS project. First one using Speeduino. I have the full ecu unit wired to the engine and I am able to read most sensor values such as TPS, IAT, CLT, etc. Output tests seem to work as well. I am having issues getting an RPM reading of any kind. Checked over my wiring and it is proper. I was previously using the Gen III LS Crank Position Sensor (24x), but after searching these forums I found users (Credit- PSIG and CjCalhoun85) who determined that the Gen III sensor, which uses 12v ref, behaves oddly when using a 5v ref supply.
So I purchased a Gen IV sensor (58x) in attempt to dodge this issue in dealing with the 12v signal coming from the 24x sensor. The Gen IV sensor uses 5v ref. Installed it onto the engine, and there is still no RPM value being picked up.
I have checked the jumpers for the Hall and VR pins on the board, and they are set for the hall setting to my understanding. I can provide pictures if needed, since I did not build this unit and am amateur at best when it comes to microelectronics.
I remember that in other mega squirt applications using this sensor (58x), they required a 1k pull-up resistor between 5v ref and the signal wire in order to detect RPM.
A) if I attempt to add the resistor in line, say at the sensor connector, will this damage my ECU unit?
B) will this work to get the 58x sensor to read RPM? Is there a definitive reason why it won’t?
Thanks for your time, will provide an update with any progress,
Built2Run
I’ve been finishing up a typical LS project. First one using Speeduino. I have the full ecu unit wired to the engine and I am able to read most sensor values such as TPS, IAT, CLT, etc. Output tests seem to work as well. I am having issues getting an RPM reading of any kind. Checked over my wiring and it is proper. I was previously using the Gen III LS Crank Position Sensor (24x), but after searching these forums I found users (Credit- PSIG and CjCalhoun85) who determined that the Gen III sensor, which uses 12v ref, behaves oddly when using a 5v ref supply.
So I purchased a Gen IV sensor (58x) in attempt to dodge this issue in dealing with the 12v signal coming from the 24x sensor. The Gen IV sensor uses 5v ref. Installed it onto the engine, and there is still no RPM value being picked up.
I have checked the jumpers for the Hall and VR pins on the board, and they are set for the hall setting to my understanding. I can provide pictures if needed, since I did not build this unit and am amateur at best when it comes to microelectronics.
I remember that in other mega squirt applications using this sensor (58x), they required a 1k pull-up resistor between 5v ref and the signal wire in order to detect RPM.
A) if I attempt to add the resistor in line, say at the sensor connector, will this damage my ECU unit?
B) will this work to get the 58x sensor to read RPM? Is there a definitive reason why it won’t?
Thanks for your time, will provide an update with any progress,
Built2Run
The bare minimum bandit has struck again.