DTC B0521: Tachometer Signal Circuit Malfunction: Description

Powertrain Control Module (PCM) supplies Instrument Panel Cluster (IPC) with information on engine RPM. IPC receives engine RPM data from PCM and serial data line, but will only display data received from PCM.

DTC B0521 will set when IPC detects that PCM has sent engine RPM information of 7400 RPM for one second. IPC will display engine RPM at 7400 RPM. No driver warning message will be displayed.

If conditions for malfunction no longer exist, history DTC will clear after 50 consecutive ignition cycles. DTC B0521 will also clear when conditions no longer exist, or when IPC or scan tool is used to clear codes.

NOTE: If DTC B0521 is a history code, problem may be intermittent. Wiggle wires while performing the following test.