B0540
DTC B0540
Circuit Description
The instrument panel cluster (IPC) receives the vehicle speed information from the powertrain control module (PCM) through the vehicle speed signal circuit. The PCM converts the data from the vehicle speed sensor to a 4000 pulses/mile signal. The PCM also sends a class 2 message to the IPC indicating the vehicle speed. If the IPC determines there is a loss of the vehicle speed signal from the PCM due to a vehicle speed signal circuit malfunction, a DTC sets.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC B0540 Speedometer Circuit
Conditions for Running the DTC
* The vehicle speed is more than 10 km/h(6 mph).
* The ignition voltage is between 9-18 volts.
Conditions for Setting the DTC
* The IPC detects that the vehicle speed signal circuit does not match the vehicle speed from the class 2 serial data circuit.
* The condition above must be present for a minimum of 5 seconds.
Action Taken When the DTC Sets
* The IPC stores a DTC B0540 in memory.
* The speedometer defaults to 0 km/h (0 mph).
* No driver warning message will be displayed for this DTC.
Conditions for Clearing the DTC
* The 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.
Test
