ICM And 7X CKP Sensor Circuit Wiring Diagram (1997 3.1L V6 Buick Century)

APPLIES TO: This ignition control module (ICM) and 7X CKP sensor circuit wiring diagram applies to the following vehicles:

• 3.1L V6 Buick Century: 1997.

The 7X CKP Sensor

The 7X crankshaft position sensor is located near the bottom rear of the engine block, underneath the rear exhaust manifold. It generates its signal by reading the crankshaft's reluctor.

The sensor connects only to the ignition control module (ICM). It does not send its signal directly to the powertrain control module (PCM).

This sensor provides the timing information the ignition control module needs to begin firing the ignition coils during engine cranking.

3X CKP SENSOR TESTS: How To Test The 7X Crankshaft Position Sensor (1994-2005 3.1L V6 Buick Century).

The Ignition Control Module (ICM)

The ignition control module is installed beneath the three ignition coils on the rear valve cover.

Besides controlling ignition coil firing during startup, the ICM also generates the 3X crankshaft reference signal that's sent to the PCM.

The PCM uses this reference signal to determine engine speed (RPM), control fuel injector operation, and calculate ignition timing. The signal consists of three digital pulses for every complete revolution of the crankshaft.

ICM DIAGNOSTIC TESTS: Testing The Ignition Module And Crank Sensor (GM 3.1L, 3.4L) (at: easyautodiagnostics.com).

Ignition Coils

There are three twin-tower ignition coils mounted directly to the ignition control module. Each one fires two spark plugs at the same time as part of the waste-spark ignition system.

Battery voltage is supplied to each ignition coil whenever the key is in the ON or START position. The ignition control module then switches the Ground circuit ON and OFF to energize each coil and produce spark.

When one of these ignition coils fails, you'll usually see one of two conditions:

• One coil tower sparks normally while the other tower doesn't.
• Neither tower produces spark because the entire coil has stopped working.

Because the coils are separate components, replacing the defective coil is all that's usually required.

IGNITION COIL TESTS: How To Test The Ignition Coil Packs (GM 3.1L, 3.4L) (at: easyautodiagnostics.com).

Other 7X CKP Sensor Wiring Diagrams

• ICM And 3X CKP Sensor Circuit Wiring Diagram (1994-1995 3.1L V6 Buick Century).
• ICM And 7X CKP Sensor Circuit Wiring Diagram (1996 3.1L V6 Buick Century).
• ICM And 7X CKP Sensor Circuit Wiring Diagram (1998-2005 3.1L V6 Buick Century).

More 3.1L V6 Buick Century Tutorials

You can find a complete list of 3.1L V6 Buick Century tutorials and wiring diagrams in this index:

• 3.1L V6 Buick Century Index of Articles.

Here's a sample of the tutorials you'll find in the index:

• How To Test The TPS With A Multimeter (1997-2005 3.1L V6 Buick Century).
• Common Causes Of Spark Plug Failure (1994-2005 3.1L V6 Buick Century).
• How To Test For A Blown Head Gasket (1994-2005 3.1L V6 Buick Century).
• How To Test Engine Compression (1994-2005 3.1L V6 Buick Century).