There are a bunch of old threads but no answer for me. I swapped a 2H for 1HZ and I'm trying to get the tach working. Not an new problem on here.
Here is what I've learned from my research. The 2H and 1HZ are both induction sensors but in different locations: bell housing in the 2H and back of the IP on the 1HZ. Induction sensors produces a pseudo AC signal (more of a square wave pulse than sine wave). The 1HZ IP gear spins at 1/2 speed of the flywheel so the pulse rate will be off. I have not tested for AC voltage from the sensor with the engine running, but I have no reason to think it is bad. I have read that I should see 0.1-0.5VAC depending on engine speed. The 2H and 1HZ wiring diagrams are similar with two sensor wires: one uninterrupted to the gauge (no ECU, etc) and the other to ground.
The tach gauge is stock 2H and I've extended the original sensor wiring so it will reach the new IP sensor. I didn't really have much hope that just plugging in would work and I was correct. The needle just sits there. Does anyone know if there is a signal converter for this application? Would replacing the gauge with a 1HZ gauge work?
Here is what I've learned from my research. The 2H and 1HZ are both induction sensors but in different locations: bell housing in the 2H and back of the IP on the 1HZ. Induction sensors produces a pseudo AC signal (more of a square wave pulse than sine wave). The 1HZ IP gear spins at 1/2 speed of the flywheel so the pulse rate will be off. I have not tested for AC voltage from the sensor with the engine running, but I have no reason to think it is bad. I have read that I should see 0.1-0.5VAC depending on engine speed. The 2H and 1HZ wiring diagrams are similar with two sensor wires: one uninterrupted to the gauge (no ECU, etc) and the other to ground.
The tach gauge is stock 2H and I've extended the original sensor wiring so it will reach the new IP sensor. I didn't really have much hope that just plugging in would work and I was correct. The needle just sits there. Does anyone know if there is a signal converter for this application? Would replacing the gauge with a 1HZ gauge work?
