[ Model - ECLIPSE CROSS / Year - 2018 ]
2018 / ECLIPSE CROSS / EC - Workshop Manual
55 -HEATER, AIR CONDITIONER AND VENTILATION > TROUBLESHOOTING > DIAGNOSIS CODE PROCEDURES > U1000 OSS CAN TIMEOUT
Code No. U1000: OSS CAN time-out
 
 
caution
  • If diagnosis code No.U1000 is set in the A/C controller assembly (A/C-ECU), diagnose the CAN main bus line.
  • Whenever the ECU is replaced, ensure that the communication circuit is normal.
 
 
TROUBLE JUDGEMENT
The A/C controller assembly (A/C-ECU) receives air conditioner control-related signals from the KOS&OSS-ECU via the CAN bus lines. If the ECU cannot receive any of the air conditioner control-related signals from the KOS&OSS-ECU, diagnosis code U1000 will be set.
 
 
 
COMMENTS ON TROUBLE SYMPTOM
Current trouble
  • Connector(s) or wiring harness in the CAN bus lines between the KOS&OSS-ECU and the A/C controller assembly (A/C-ECU), the power supply system to the KOS&OSS-ECU, the KOS&OSS-ECU itself, or the A/C controller assembly (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 controller assembly (A/C-ECU) and the KOS&OSS-ECU, and the power supply system to the KOS&OSS-ECU. For diagnosis procedures, refer to "How to treat past trouble" (Refer to GROUP 00 - How to Treat Past Trouble ).
    noteFor a past trouble, you can not find it by the M.U.T.-IIISE CAN bus diagnostics even if there is any failure in CAN bus lines. In this case, refer to GROUP 00, 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 diagnosis code, which is set regarding the CAN communication-linked ECUs (Refer to GROUP 54C - CAN Bus Line Diagnostic Flow ).
    cautionIf the ignition switch is turned to the ON position without starting the engine, diagnosis code U1000 (past trouble) may be set in the A/C controller assembly (A/C-ECU) after three minutes.
 
 
 
PROBABLE CAUSES
  • Damaged wiring harness or connectors
  • Malfunction of the KOS&OSS-ECU
  • Malfunction of the A/C controller assembly (A/C-ECU)
 
 
 
 
DIAGNOSIS PROCEDURE
STEP 1. M.U.T.-IIISE CAN bus diagnostics
Use the M.U.T.-IIISE to diagnose the CAN bus lines.
Is the check result normal?
Go to Step 2.
Repair the CAN bus lines (Refer to GROUP 54C, Troubleshooting ).
 
STEP 2. M.U.T.-IIISE other system diagnosis code
Check if diagnosis code is set in the KOS&OSS-ECU.
Is the diagnosis code set?
Diagnose the KOS&OSS-ECU. Refer to GROUP 42B, Troubleshooting .
Go to Step 3.
 
STEP 3. M.U.T.-IIISE other system diagnosis code
Check if a diagnosis code, which relates to CAN communication-linked systems below, is set.
  • Combination meter
    U1000: OSS CAN timeout
Is the diagnosis code set?
Go to Step 4.
Go to Step 5.
 
STEP 4. Check whether the diagnosis code is set again.
Recheck if the diagnosis code is set.
(1) Erase the diagnosis code.
(2) Ignition switch: "LOCK" (OFF) to "ON"
(3) Check if the diagnosis code is set.
Is the diagnosis code set?
Replace the KOS&OSS-ECU.
A poor connection, open circuit or other intermittent malfunction in the CAN bus line between the KOS&OSS-ECU and the A/C controller assembly (A/C-ECU) (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).
 
STEP 5. Check whether the diagnosis code is set again.
Recheck if the diagnosis code is set.
(1) Erase the diagnosis code.
(2) Ignition switch: "LOCK" (OFF) to "ON"
(3) Check if the diagnosis code is set.
Is the diagnosis code set?
Replace the A/C controller assembly (A/C-ECU).
A poor connection, open circuit or other intermittent malfunction in the CAN bus line between the KOS&OSS-ECU and the A/C controller assembly (A/C-ECU) (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).