Code No.U1110 A/C CAN timeout/Not equipped
caution |
- If diagnosis code No.U1110 is set in the ETACS-ECU, diagnose the CAN main bus line.
- Whenever the ECU is replaced, ensure that the input and output signal circuits are normal.
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TROUBLE JUDGEMENT
If signal from the A/C-ECU cannot be received for 2500 milliseconds or more, the ETACS-ECU sets diagnosis code No. U1110.
PROBABLE CAUSES
- Malfunction of the A/C-ECU
- Malfunction of the ETACS-ECU
- Malfunction of the CAN bus
DIAGNOSIS PROCEDURE
STEP 1. M.U.T.-III CAN bus diagnostics
Use the M.U.T.-III to diagnose the CAN bus lines.
Q.
Is the check result normal?
Go to Step 2.
Repair the CAN bus line (Refer to GROUP 54C - Troubleshooting
).
STEP 2. Check the M.U.T.-III Diagnosis code for other systems
Check that the A/C-ECU set a diagnosis code.
Q.
Is the diagnosis code set?
Diagnose the A/C-ECU (Refer to GROUP 55B, Troubleshooting
).
Go to Step 3.
STEP 3. Check whether the diagnosis code is set again.
Check again if the diagnosis code is set in the ETACS-ECU.
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(1)Erase the diagnosis code.
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(2)Turn the ignition switch from "LOCK" (OFF) position to "ON" position.
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(3)On completion, check that the diagnosis code is set again.
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Q.
Is the diagnosis code set?
Replace the A/C-ECU (Refer to GROUP 55B - Heater Control Unit
). After replacing the ECU, carry out the CAN bus diagnostics. Then go to Step 4.
A poor connection, open circuit or other intermittent malfunction is present in the CAN bus lines between the A/C-ECU and the ETACS-ECU (Refer to GROUP 00, How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions
).
STEP 4. Check whether the diagnosis code is set again.
Check again if the diagnosis code is set in the ETACS-ECU.
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(1)Erase the diagnosis code.
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(2)Turn the ignition switch from "LOCK" (OFF) position to "ON" position.
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(3)On completion, check that the diagnosis code is not set again.
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Q.
Is the diagnosis code set?
Replace the ETACS-ECU (Refer to
). After replacing the ECU, carry out the CAN bus diagnostics. Then go to Step 5.
A poor connection, open circuit or other intermittent malfunction is present in the CAN bus lines between the A/C-ECU and the ETACS-ECU (Refer to GROUP 00, How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions
).
STEP 5. Check whether the diagnosis code is set again.
Recheck if the diagnosis code is set in the ETACS-ECU.
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(1)Erase the diagnosis code.
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(2)Turn the ignition switch from "LOCK" (OFF) position to "ON" position.
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(3)On completion, check that the diagnosis code is set again.
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Q.
Is the diagnosis code set?
Return to Step 1.
The procedure is complete.