Circuit Description
The powertrain control module (PCM) creates the engine speed signal by pulsing the signal circuit to ground at the rate of 2 pulses per engine revolution. The instrument panel cluster (IPC) converts the signal to a tachometer position. The IPC also receives a class 2 message from the PCM indicating the engine speed. The IPC uses this class 2 message for diagnostic purposes.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC B0560 Tachometer Circuit
Conditions for Running the DTC
| • | The IPC receives a class 2 message from the PCM indicating that 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 a DTC B0560 in memory.
Conditions for Clearing the DTC
| • | A history DTC clears after 100 malfunction free warm-up cycles. |
| • | The DTC becomes history when the conditions for setting the DTC are no longer present. |
| • | The IPC receives the clear code command from the scan tool. |
Step | Action | Values | Yes | No |
|---|---|---|---|---|
Schematic Reference: Instrument Cluster Schematics Connector End View Reference: Master Electrical Component List in Wiring Systems | ||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
2 |
Does the Engine Speed parameter match the tachometer display? | -- | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | Go to Step 3 |
3 |
Does the voltage measure greater than the specified value? | 9 V | Go to Step 4 | Go to Step 5 |
4 | Test the engine speed signal circuit for a short to voltage. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 10 | Go to Step 6 |
5 | Test the engine speed signal circuit for an open or for a short to ground. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 10 | Go to Step 7 |
6 | Inspect for poor connections at the harness connector of the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 10 | Go to Step 8 |
7 | Inspect for poor connections at the harness connector of the instrument panel cluster (IPC). Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 10 | Go to Step 9 |
8 | Replace the PCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 10 | -- |
9 | Replace the IPC. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 10 | -- |
10 |
Does the DTC reset? | -- | Go to Step 2 | System OK |
