DTC 41

Code 41 Chart:

Wiring Diagram:

CIRCUIT DESCRIPTION:

The tach signal, to the ECM (12 volts), will vary as the ignition coil is toggled to ground. The ECM uses this signal to send a pulse to the fuel injector. A Code 41 will set if there is no signal, or a constant voltage on the line.

TEST DESCRIPTION: The numbers below refer to circled numbers on the diagnostic chart.

1. Test for B+ on signal line.

2. Test noise suppressor for open.

3. Test for toggling voltage signal.

DIAGNOSTIC AIDS:

A poor or loose connection will set a Code 41. A visual inspection will verify all connections. This prevents setting a false trouble code to the ECM.