Fault code 115 is active and I changed out the speed sensor and still acts the same. Wire A has 5 volts with the key on, wire C has a signal at the computer while it’s running. When key is on wire A&B have 5 volts like it should. Anything that I’m missing?
Circuit Description The engine speed sensor provides engine speed information to the electronic control module (ECM). The sensor must be powered up by (+) 5 VDC to operate. The sensor generates its signals by sensing the movement of target teeth machined into a tone wheel that is mounted to the crankshaft. The tone wheel has 35 teeth and a gap where the 36th tooth would be placed. This missing tooth indicates that cylinder 1 (and 6) is at top dead center. Component Location The engine speed/position sensor is located on the intake side of the engine block, between cylinders 4 and 5. Shop Talk This fault code will also cause a fuel derate. This could be the cause of low-power complaint. Also, this fault code can cause starting problems in cold weather.
Pin B should be ground (return) The 5V power is shared by other sensors also. Perhaps you have a bad harness to another sensor, and are losing the 5V power. Sounds like you have some signal at the ECM from your speed sensor. Try unplugging your engine position sensor, and see what happens. Might have a bad signal coming from the other speed sensor. Any other fault codes? I'm assuming your engine is de-rated
1. Engine Air Inlet 2. VP44 Connector 3. 23-pin OEM Connector 4. High-Pressure Fuel Lines 5. Intake Manifold 6. VP44 Relay-OEM Mounted 7. 3/4 NPTF (in) Water Heater (optional) 8. Magnetic Pickup Location 3/4 to 16 UNF 9. Fuel Inlet Connection 10. Fuel Lift Pump 11. WIF Sensor 12. Crankcase Breather 13. Engine Position Sensor (EPS) 14. Fuel Filter/Water Separator 15. Oil Pressure Sensor 16. Fuel Water Drain 17. Electronic Control Module (ECM) 18. 1/8 NPTF (in) Oil Pressure 19. Engine Position Sensor 20. Engine Dataplate 21. Fuel Injection Pump 22. Intake Air Preheater (optional)