B0560

DTC B0560

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using the diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.

DTC Descriptor
DTC B0560
- Tachometer Circuit

Diagnostic Fault Information





Circuit 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 engine speed is greater than 800 RPM.
* The ignition voltage is between 9-18 volts.

Conditions for Setting the DTC

* The IPC detects that the engine speed signal circuit does not match the engine speed from the serial data circuit.
* The above condition is present for at least 5 seconds.

Action Taken When the DTC Sets

The IPC stores the DTC in memory.

Conditions for Clearing the DTC

* A last test failed (current DTC) clears when the diagnostic runs and does not fail.
* A history DTC clears after 40 malfunction-free warm-up cycles.

Reference Information
Schematic Reference

Instrument Cluster Schematics (Instrument Cluster Schematics)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Instrument Cluster Description and Operation (Description and Operation)
Electrical Information Reference

* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)

Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector X1 at the ECM. Install a signal generator and instrument panel tester between the engine speed signal circuit terminal 25 and ground.
2. Ignition ON, set the signal generator to generate a tachometer signal. Verify that the tachometer indicates an RPM reading.

• If no RPM reading is present, test the signal circuit for a short to voltage, a short to ground or an open/high resistance. If the circuit tests normal, replace the IPC.

3. If all circuits test normal, test or replace the ECM.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

Control Module References (Programming and Relearning) for the ECM and IPC replacement, setup, and programming