DTC 13
DTC 013: A/C-ECU Time-outCircuit Of Time-Out During CAN Communication With A/C-ECU Part 1:
Circuit Of Time-Out During CAN Communication With A/C-ECU Part 2:
CAUTION:
- If DTC 013 is set in the multi-center display, always diagnose the CAN bus lines.
- Whenever the ECU is replaced, ensure that the communication circuit is normal.
CIRCUIT OPERATION
The multi-center display unit (middle grade type) communicates with the A/C-ECU via CAN bus lines.
DTC SET CONDITION
When the multi-center display unit (middle grade type) can not receives necessary signals from the A/ C-ECU via CAN bus lines. If the display unit can not receives the necessary A/C-ECU signals, DTC 013 will be set.
TECHNICAL DESCRIPTION (COMMENT)
CAUTION: If the ignition switch is turned to the ON position without starting the engine, DTC (past trouble) 011, 012 and 014 may be set to the combination meter (incorporating meter-ECU) after three minutes.
Current trouble
- Connector(s) or wiring harness in the CAN bus lines between the A/C-ECU and the multi-center display unit (middle grade type), the power supply system to the display unit, the display unit itself, or the A/C-ECU may be defective.
Past trouble
- Carry out diagnosis with particular emphasis on connector(s) or wiring harness in the CAN bus lines between the A/C-ECU and the multi-center display unit (middle grade type), and the power supply system to the A/C-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 any 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 A/C-ECU.
- Malfunction of multi-center display unit (middle grade type).
DIAGNOSIS
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
- MB991911: M.U.T.-III Main Harness A (Vehicles with CAN communication system)
STEP 1. Using scan tool MB991958, diagnose the CAN bus line.
Use scan tool MB991958 to diagnose the CAN bus lines.
1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to "ON" position.
3. Diagnose the CAN bus line.
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). On completion, go to Step 6.
STEP 2. Using scan tool MB991958, read the A/C diagnostic trouble code
Check if an A/C system DTC is set.
Q: Is the DTC set?
YES: Diagnose the A/C system by referring to Manual A/C Diagnosis - Diagnostic Trouble Code Chart Diagnostic Trouble Code Descriptions or Auto A/C Diagnostic Trouble Code Chart. Diagnostic Trouble Code Descriptions
NO: Go to Step 3.
STEP 3. Using scan tool MB991958, read the diagnostic trouble code.
Check if a DTC, which relates to CAN communication-linked systems below, is set.
Powertrain control module
- DTC U1110: A/C-ECU time-out
ETACS-ECU
- DTC 013: A/C-ECU time-out
Q: Is the DTC set?
YES: Go to Step 4.
NO: Go to Step 5.
STEP 4. Recheck for diagnostic trouble code.
Recheck if the DTC is set.
1. Erase the DTC.
2. Turn the ignition switch to "ON" position.
3. Check if the DTC is set.
Q: Is the check result satisfactory?
YES: A poor connection, open circuit or other intermittent malfunction is present in the CAN bus lines between the A/C-ECU and the middle grade multi-center display unit (Refer to How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction).
NO: Replace A/C-ECU and then go to step 6.
STEP 5. Recheck for diagnostic trouble code.
Recheck if the DTC is set.
1. Erase the DTC.
2. Turn the ignition switch to "ON" position.
3. Check if the DTC is set.
Q: Is the check result satisfactory?
YES: A poor connection, open circuit or other intermittent malfunction is present in the CAN bus lines between the A/C-ECU and the middle grade multi-center display unit (Refer to How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction).
NO: Replace the multi-center display unit (middle grade type) and then go to step 6.
STEP 6. Recheck for diagnostic trouble code.
Recheck if the DTC is set.
1. Erase the DTC.
2. Turn the ignition switch to "ON" position.
3. Check if the DTC is set.
Q: Is the check result satisfactory?
YES: the procedure is complete.
NO: Go to Step 1.