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 Yukon, 1994 GMC Suburban, 1994 GMC Pickup, 1994 GMC Cab & Chassis, and 1994 GMC C3500 HD. 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.