P0725

DTC P0725: Engine speed signal abnormality

CAUTION
^ If there is any problem in the CAN bus lines, an incorrect diagnostic trouble code may be set. Prior to this diagnosis, diagnose the CAN bus lines.
^ Whenever the ECU is replaced, ensure that the CAN bus lines are normal.

DIAGNOSTIC FUNCTION
TC-SST-ECU receives the periodic communication data from the engine control module via the CAN bus lines, and checks the data for abnormality.

DESCRIPTIONS OF MONITOR METHODS
The engine speed signal from the engine control module is determined to be abnormal.

PROBABLE CAUSES
^ The CAN bus line is defective.
^ Malfunction of crankshaft position sensor
^ Malfunction of engine control module
^ Malfunction of TC-SST-ECU

DIAGNOSTIC PROCEDURE

Required Special Tools:
^ MB991958: Scan Tool (M.U.T.-III Sub Assembly)
^ MB991824: Vehicle Communication Interface (V.C.I.)
^ MB991827: M.U.T.-III USB Cable
^ MB991910: M.U.T.-III Main Harness A

STEP 1. Scan tool CAN bus diagnostics
Using the scan tool, diagnose the CAN bus lines.
Q: Is the check result normal?
YES: Go to Step 2.
NO: Repair the CAN bus lines. After repairing the CAN bus line, go to Step 2.

STEP 2. Scan tool diagnostic trouble code
Check the engine diagnostic trouble code. Diagnostic Trouble Code Descriptions
Q: Is the DTC set?
YES: Perform the relevant troubleshooting.
NO: Go to Step 3.

STEP 3. Check whether the DTC is reset.
After 10 or more seconds have passed with the engine idle status, check that the DTC is reset.
Q: Is DTC No. P0725 set?
YES: Replace the mechatronic assembly.
NO: Intermittent malfunction.