DTC 19, Crankshaft Position Reference Error: Notes
WARNING: This page does not describe the selected car, but rather 10 other vehicles, including the 1995 GMC Yukon, 1995 GMC Suburban, 1995 GMC Pickup, 1995 GMC Cab & Chassis, and 1995 GMC C3500 HD. However, it is still accessible from the selected car via links, so may be relevant.
Crankshaft position sensor is a Hall Effect type sensor that monitors crankshaft position and speed There are 4 teeth 90 degrees apart on front of crankshaft sprocket that induce an alternating current in sensor which is transmitted to PCM. DTC 19 will set when 8 crankshaft position pulses are missed for every cam reference pulse. PCM will default to backup fuel.
NOTE:
Test numbers refer to numbers on diagnostic chart.
- This step determines if DTC 19 is result of a hard failure or an intermittent condition.
- This step checks 5-volt reference circuit.
- This step checks ground circuit.
- This step checks sensor and harness wiring.