Vehicles With ABS
DTC 25: Wrong-diameter TireABS SENSOR SYSTEM CIRCUIT
Refer to Vehicles With ABS. Vehicles With ABS
CIRCUIT OPERATION
The AWD-ECU receives each ABS sensor signal through the ABS-ECU to detect the tire conditions.
DTC SET CONDITIONS
DTC 25 is set as wrong-diameter tire when one of the four vehicle speeds is outside the range of specified values in respect to the average of the four vehicle speed sensors, when the vehicle speed is above 20 km/h (12 mph) with the steering wheel in the straight ahead position. However the warning light does not light up.
TROUBLESHOOTING HINTS (THE MOST LIKELY CAUSES FOR THIS CODE TO BE SET ARE:)
^ Malfunction of the tire
^ Malfunction of the ABS sensor
^ Damaged harness and connector
^ Malfunction of the ABS-ECU
^ Malfunction of the AWD-ECU
DIAGNOSIS
Required Special Tool:
^ MB991958: Scan Tool (M.U.T-III Sub Assembly)
^ MB991824: V.C.I.
^ MB991827: USB Cable
^ MB991911: Main Harness B
STEP 1. Check the tire.
Check the tire pressure, size and brand.
Q: Is the check result normal?
YES: Go to Step 2.
NO: Adjust or replace the tire.
STEP 2. Using scan tool MB991958, read the ABS diagnostic trouble code.
CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the LOCK (OFF) position before connecting or disconnecting scan tool MB991958.
1) Connect scan tool MB991958 to the data link connector.
2) Turn the ignition switch to the ON position.
3) Check for ABS diagnostic trouble code.
4) Turn the ignition switch to the LOCK (OFF) position.
Q: Are DTCs (No.11, 12, 13, 14, 21, 22, 23, 24) set?
YES: Refer to ABS-Diagnostic Trouble Code Chart.
NO: Go to Step 3.
STEP 3. Using scan tool MB991958, read the ACD diagnostic trouble code.
1) Connect scan tool MB991958 to the data link connector.
2) Turn the ignition switch to the ON position.
3) Check for ACD diagnostic trouble code.
4) Turn the ignition switch to the LOCK (OFF) position.
Q: Are DTCs (No.21, 22, 23, 24) set?
YES: Refer to DTCs 21, 22, 23, 24: ABS Sensor System. Vehicles With ABS
NO: Go to Step 4.
STEP 4. Using scan tool MB9911958, check data list item 01, 02, 03, 04: ABS Sensor.
1) Connect scan tool MB991958 to the data link connector.
2) Start the engine.
3) Set scan tool MB991958 to the data reading mode.
^ Item 01: ABS Sensor
^ Item 02: ABS Sensor
^ Item 03: ABS Sensor
^ Item 04: ABS Sensor
4) Turn the ignition switch to the LOCK (OFF) position.
Q: Is the sensor operating properly?
YES: It can be assumed that this malfunction is intermittent.
NO: Replace the AWD-ECU.