Circuit Description
The IC module supplies the tachometer signal to the Instrument Cluster. When the vehicle is started the 7X CKP sensor produces a signal that is received by the IC Module, the module then generates a reference pulse known as the 3X Reference circuit. The module sends this reference signal to the PCM to perform other ignition functions, and to the Instrument Cluster for the tachometer signal.
Diagnostic Aids
Refer to Instrument Cluster System Check in Instrument Panel, Gauges and Console for additional diagnostic information.
Inspect for the following conditions:
Many situations may lead to an intermittent condition. Perform each inspection or test as directed.
Important: : Remove any debris from the connector surfaces before servicing a component. Inspect the connector gaskets when diagnosing or replacing a component. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion.
| • | Loose terminal connection |
| - | Use a corresponding mating terminal to test for proper tension. Refer to Testing for Intermittent Conditions and Poor Connections , and to Connector Repairs in Wiring Systems for diagnosis and repair. |
| - | Inspect the harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and faulty terminal to wire connection. Refer to Testing for Intermittent Conditions and Poor Connections , and to Connector Repairs in Wiring Systems for diagnosis and repair. |
| • | Damaged harness--Inspect the wiring harness for damage. If the harness inspection does not reveal a problem, observe the display on the scan tool while moving connectors and wiring harnesses related to the sensor. A change in the scan tool display may indicate the location of the fault. Refer to Wiring Repairs in Wiring Systems for diagnosis and repair. |
| • | Inspect the powertrain control module (PCM) and the engine grounds for clean and secure connections. Refer to Wiring Repairs in Wiring Systems for diagnosis and repair. |
If the condition is determined to be intermittent, reviewing the Snapshot or Freeze Frame/Failure Records may be useful in determining when the DTC or condition was identified.
Step | Action | Value(s) | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
1 | Did you perform the Instrument Cluster System Check in Instrument Panel, Gauges, and Console? | -- | Go to Instrument Cluster System Check in Instrument Panel, Gauges and Console | |||||||
2 | Did you perform the Engine Controls Diagnostic System Check? | -- | ||||||||
3 |
Does the scan tool engine rpm indicate approximate engine operation? | -- | ||||||||
4 | Monitor Tachometer reading on the instrument cluster, and compare with RPM on scan tool. Do they closely match each other? | -- | ||||||||
5 |
Did you find and correct the condition? | -- | ||||||||
6 | Diagnose the Instrument Panel Cluster Tachometer gauge. Refer to Tachometer Inoperative . Did you find and correct the condition? | -- | ||||||||
7 |
Did you find and correct the condition? | -- | ||||||||
8 | Replace the PCM. Refer to Powertrain Control Module Replacement/Programming . Did you complete the repair? | -- | ||||||||
9 | Operate the vehicle while observing the I/P tachometer. Does the I/P tachometer operate properly? | -- | Go to Diagnostic Aids | |||||||
10 | Does the scan tool display any DTCs that you have not diagnosed? | -- | System OK |
