Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptor
DTC B0560: Tachometer CircuitDiagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage |
|---|---|---|---|
Engine Speed Signal | B0560 | B0560 | B0560 |
Circuit/System Description
The engine control module (ECM) creates the engine speed signal by pulsing the engine speed signal circuit to ground at a rate of 2 pulses per engine revolution. The instrument panel cluster (IPC) converts the engine speed signal to a tachometer position to indicate the engine speed. The IPC also receives from the ECM a serial data message indicating the engine speed. The IPC uses the serial data engine speed information from the ECM for diagnostic purposes.
Conditions for Running the DTC
| • | The IPC receives a serial data message from the ECM indicating the engine speed is greater than 800 RPM. |
| • | The ignition voltage is between 9-18 volts. |
Conditions for Setting the DTC
| • | The IPC does not detect a 2 pulses per engine revolution signal on the engine speed signal circuit. |
| • | The above condition is present for at least 5 seconds. |
Action Taken When the DTC Sets
The IPC stores DTC B0560 in memory.
Conditions for Clearing the DTC
| • | The DTC becomes history when the conditions for setting the DTC are no longer present. |
| • | The history DTC clears after 40 malfunction-free warm-up cycles. |
Reference Information
Schematic Reference
Connector End View Reference
Description and Operation
Instrument Cluster Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information.
Circuit/System Testing
- Ignition ON, the scan tool installed, perform the IPC Gage Sweep Test in the IPC Output Controls. Verify the tachometer dial moves from the minimum to the maximum position and back to the tachometer minimum position.
- Ignition OFF, disconnect the X1 harness connector at the ECM.
- Ignition ON, test for 9-11 volts between the engine speed signal circuit terminal 48 and ground.
- If all circuits test normal, test or replace the ECM.
| ⇒ | If the tachometer does not perform the IPC Gage Sweep Test, replace the IPC. |
| ⇒ | If less than 9 volts, test the circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the IPC. |
| ⇒ | If greater than 11 volts, test the circuit for a short to voltage. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for the ECM or IPC replacement, setup and programming
