DTC 19 - Crankshaft Position Reference Error: Notes
WARNING: This page does not describe the selected car, but rather 10 other vehicles, including the 1994 GMC Vandura Special, 1994 GMC Vandura, 1994 GMC Rally Camper Special, 1994 GMC Rally, and 1994 GMC Forward Control. However, it is still accessible from the selected car via links, so may be relevant.
The crankshaft position sensor is a hall effect type sensor that monitors crankshaft position and speed There are 4 teeth 90 degrees apart on the front of the crankshaft sprocket that induce an alternating current in the sensor which is transmitted to the 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 the result of a hard failure or an intermittent condition.
- This step checks the 5-volt reference circuit.
- This step checks the ground circuit.
- This step checks the sensor and harness wiring.