DTC 14
DTC 14: ABS Sensor (Open Circuit or Short Circuit)
CIRCUIT OPERATION
^ A toothed ABS rotor generates a voltage pulse as it moves across the pickup field of each ABS sensor.
^ The amount of voltage generated at each wheel is determined by the clearance between the ABS rotor teeth and the ABS sensor, and by the speed of rotation.
^ The ABS sensors transmit the frequency of the voltage pulses and the amount of voltage generated by each pulse to the ABS electronic control unit (ABS-ECU).
^ The ABS hydraulic unit modulates the amount of braking force individually applied to each wheel cylinder.
ABS DTC SET CONDITIONS
DTCs 11, 12, 13, 14 are output when signal is not input due to breakage of the wires of one or more of the four ABS sensors.
TROUBLESHOOTING HINTS (THE MOST LIKELY CAUSES FOR THESE DTCS ARE TO SET ARE:)
^ Malfunction of the ABS sensor
^ Damaged wiring harness or connector
^ Malfunction of the hydraulic unit (integrated with ABS-ECU)
DIAGNOSIS
Required Special Tools:
^ MB991223: Harness Set
^ MB991958: Scan Tool (MUT-III Sub Assembly)
^ MB991824: Vehicle Communication Interface
^ MB991327: MUT-III USB Cable
^ MB991910: MUT-III Main Harness A
^ MB991529: Diagnostic Trouble Code Check Harness
STEP 1. Using scan tool MB991958, check data list.
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. Start the engine.
3. Set scan tool MB991958 to the data reading mode, and check the data list items by driving the vehicle.
^ Item 11 (DTC 11 is set): Front right ABS sensor
^ Item 12 (DTC 12 is set): Front left ABS sensor
^ Item 13 (DTC 13 is set): Rear right ABS sensor
^ Item 14 (DTC 14 is set): Rear left ABS sensor
4. Turn the ignition switch to the LOCK (OFF) position.
Q: Is the ABS sensor input normal?
YES: This malfunction is intermittent.
NO: Go to Step 2.
STEP 2. Inspect the ABS sensor.
Check items:
^ ABS sensor internal resistance: 1.24 - 1.64 k Ohms
^ Insulation between the ABS sensor body and the connector terminals
Q: Is the ABS sensor damaged?
YES: Replace it and then go to Step 8.
NO: Go to Step 3.
STEP 3. Check ABS sensor circuit at the ABS-ECU connector B-03.
1. Disconnect the connector B-03 and measure at the harness side.
2. Measure the resistance between the ABS-ECU connector terminals 16 and 26, 9 and 10, 11 and 17, or 27 and 28.
Standard Value: 1.24 - 1.64 k Ohms
Q: Is the resistance between terminals 16 and 26, 9 and 10, 27 and 28, or 11 and 17 within the standard value?
When resistances between all terminals are within the standard value.: Erase the DTC memory, and recheck if any DTC sets. If DTC 11, 12, 13 or 14 sets, replace the hydraulic unit (integrated with ABS-ECU). Then go to Step 8.
When resistance between terminals 16 and 26 is not within the standard value.: Go to Step 4.
When resistance between terminals 9 and 10 is not within the standard value.: Go to Step 5.
When resistance between terminals 27 and 28 is not within the standard value.: Go to Step 6.
When resistance between terminals 11 and 17 is not within the standard value.: Go to Step 7.
STEP 4. Check the harness wires between ABS-ECU connector B-03 terminal 16 and ABS sensor
NOTE: After inspecting ABS-ECU connector B-03, intermediate connector A-14 and ABS sensor
Q: Is the harness wire between ABS-ECU connector B-03 terminal 16 and ABS sensor
YES: Repair it and go to Step 8.
NO: Go to Step 8.
STEP 5. Check the harness wires between ABS-ECU connector B-03 terminal 10 and ABS sensor
NOTE: After inspecting ABS-ECU connector B-03, intermediate connector C-14, C-104 and ABS sensor
Q: Is the harness wire between ABS-ECU connector B-03 terminal 10 and ABS sensor
YES: Repair it and go to Step 8.
NO: Go to Step 8.
STEP 6. Check the harness wires between ABS-ECU connector B-03 terminal 28 and ABS sensor
NOTE: After inspecting ABS-ECU connector B-03, intermediate connector C-104, C-117, D-22 and ABS sensor
Q: Is the harness wire between ABS-ECU connector B-03 terminal 28 and ABS sensor
YES: Repair it and then go to Step 8.
NO: Go to Step 8.
STEP 7. Check the harness wires between ABS-ECU connector B-03 terminal 11 and ABS sensor
NOTE: After inspecting ABS-ECU connector B-03, intermediate connector C-104, C-117, D-22 and ABS sensor
Q: Is the harness wire between ABS-ECU connector B-03 terminal 11 and ABS sensor
YES: Repair it and then go to Step 8.
NO: Go to Step 8.
STEP 8. Recheck for diagnostic trouble codes.
Q: Is DTC 11, 12, 13 or 14 output?
YES: Go to Step 1.
NO: The procedure is complete.