U1114
DTC U1114: TPMS-ECU time-outCAUTION:
- If DTC U1114 is set in the combination meter, always diagnose the CAN bus lines.
- Whenever the ECU is replaced, ensure that the communication circuit is normal.
CIRCUIT OPERATION
Some instruments of the combination meter are linked to the CAN bus line. Both the combination meter and the ECM
DTC SET CONDITION
The combination meter communicates with the TPMS-ECU through CAN bus lines. If it cannot receive all the necessary signals from the SRS-ECU, DTC U1114 is set.
TECHNICAL DESCRIPTION (COMMENT)
Current trouble
- Connector(s) or wiring harness in the CAN bus lines between the TPMS-ECU and the combination meter, the power supply system to the TPMS-ECU, the TPMS-ECU itself, or the combination meter may be defective.
Past trouble
- Carry out diagnosis with particular emphasis on connector(s) or wiring harness in the CAN bus lines between the TPMS-ECU and the combination meter, and the power supply system to the TPMS-ECU. For diagnosis procedures, refer to "How to cope with past trouble" (Refer to How to Use Troubleshooting/Inspection Service Points).
NOTE: For a past trouble, you may not find it by the M.U.T.-III CAN bus diagnostics even if there is a failure in CAN bus lines. In this case, refer to How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction.) and check the CAN bus lines. You can narrow down the possible cause of the trouble by referring to the DTC, which is set regarding the CAN communication-linked ECUs (Refer to Information Bus - CAN bus line Diagnostics Flow).
TROUBLESHOOTING HINTS
- The wiring harness or connectors may have loose, corroded, or damaged terminals, or terminals pushed back in the connector.
- Malfunction of TPMS-ECU
- Malfunction of combination meter
DIAGNOSIS
Required Special Tools:
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: M.U.T.-III USB Cable
- MB991910: M.U.T.-III Main Harness A
STEP 1. Using scan tool MB991958, diagnose the CAN bus line.
Use scan tool MB991958 to diagnose the CAN bus lines.
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 "ON" position.
3. Diagnose the CAN bus line.
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the check result satisfactory?
YES: Go to Step 2.
NO: Repair the CAN bus lines (Refer to Information Bus, Diagnosis-Can Bus Diagnostic Chart).
STEP 2. Using scan tool MB991958, read the TPMS diagnostic trouble code.
Check that the TPMS-ECU sets a diagnostic trouble code.
1. Turn the ignition switch to "ON" position.
2. Read the diagnostic trouble code.
3. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC set?
YES: Refer to Tire and Wheel - Diagnosis - Diagnostic Trouble Code Chart.
NO: Go to Step 3.
STEP 3. Recheck for diagnostic trouble code.
Recheck if the diagnostic trouble code is set.
1. Turn the ignition switch to "ON" position.
2. Erase the diagnostic trouble code.
3. Turn the ignition switch to the "LOCK" (OFF) position.
4. Turn the ignition switch to "ON" position.
5. Check if the diagnostic trouble code is set.
6. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the check result satisfactory?
YES: A poor connection, open circuit or other intermittent malfunction is present in the lines between the SRS-ECU and the combination meter (Refer to How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction).
NO: Replace the combination meter.