DTC 17

Trouble Code Chart 17:

Camshaft And Crankshaft Sensor Wiring:

CIRCUIT DESCRIPTION
The cam sensor is a "Hall-effect" switch, located on the front of of the engine, is supplied ignition voltage and has its own ground. The cam sensor sends a signal to the ECM when the #1 cylinder is on the compression stroke. This signal is used by the ECM to synchronize Sequential Fuel Injection (SFI) mode of operation with the intake valve opening. If the cam signal is not received by the ECM, the ECM will still operate in SFI mode based on the reference signal, however, SFI mode timing may not be as accurate because the ECM does not know the exact time the intake valve is opening. A loss of this signal or extra cam signals, above 500 RPM, to the ECM will set a DTC 17.

TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.

1. The ECM performs a test for DTC 17 when the engine is running or during cranking.

DTC 17 will set when:
^ Cam pulse is missing on the first pass through the internal ECM self test of the cam sensor.
OR
^ Cam pulse is missing for 3 seconds.

2. By repeatedly "tapping" the starter the camshaft timing mark and the camshaft sensor will align with each other. At this point, the voltage through the sensor and onto the ECM should drop to near zero temporarily. This indicates that the camshaft sensor is capable of sending a signal to the ECM.

3. Before replacing the cam sensor, inspect the sensor for proper installation.

DIAGNOSTIC AIDS:
An intermittent cam signal can be caused by poor connections, cracked sensor or internal engine problem.