Code No.U1102: ABS-ECU Time-out

caution

If diagnosis code U1102 is set in the combination meter, always diagnose the CAN bus lines.

caution

Whenever the ECU is replaced, ensure that the communication circuit is normal

TROUBLE JUDGMENT

The combination meter communicates with the ABS-ECU through CAN bus lines. If it can not receive all the necessary signals from the ABS-ECU, diagnosis code U1102 is set.

COMMENTS ON TROUBLE SYMPTOM

Current trouble

Connector(s) or wiring harness in the CAN bus lines between the ABS-ECU and the combination meter, the power supply system to the ABS-ECU, the ABS-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 ABS-ECU and the combination meter, and the power supply system to the ABS-ECU. For diagnosis procedures, refer to "How to cope with past trouble" (Refer to GROUP 00, 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 GROUP 00, How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions

). 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 54F, Explanation about the M.U.T.-III CAN Bus Diagnostics

caution

If the ignition switch is turned to the ON position without starting the engine, diagnosis code (past trouble) U1100, U1101 may be set on the combination meter after one minutes.

PROBABLE CAUSES

Damaged harness wires and connectors
Malfunction of ABS-ECU
Malfunction of combination meter

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 satisfactory?

	Go to Step 2.

	Repair the CAN bus lines (Refer to GROUP 54F, Diagnosis - Can Bus Diagnostic Table ). On completion, go to Step 6.

STEP 2. M.U.T.-III other system diagnosis code

Check that the ABS-ECU sets a diagnosis code.

Q. Is the diagnosis code set?

	Diagnose the ABS. Refer to GROUP 35B, Troubleshooting - Inspection Chart for Diagnosis Code .

	Go to Step 3.

STEP 3. M.U.T.-III other system diagnosis code

Check if a diagnosis code, which relates to CAN communication-linked systems below, is set.

MPI

U1102: ABS-ECU time-out

Q. Is the diagnosis code set?

	Go to Step 4.

	Go to Step 5.

STEP 4. Check whether the diagnosis code is reset.

Recheck if the diagnosis code is set.

(1)Erase the diagnosis code.

(2)Turn the ignition switch to "ON" position.

(3)Check if the diagnosis code is set.

Q. Is the check result satisfactory?

	A poor connection, open circuit or other intermittent malfunction is present in the lines between the ABS-ECU and the combination meter (Refer to GROUP 00, How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).

	Replace ABS-ECU and then go to step 6.

STEP 5. Check whether the diagnosis code is reset.

Recheck if the diagnosis code is set.

(1)Erase the diagnosis code.

(2)Turn the ignition switch to "ON" position.

(3)Check if the diagnosis code is set.

Q. Is the check result satisfactory?

	A poor connection, open circuit or other intermittent malfunction is present in the lines between the ABS-ECU and the combination meter (Refer to GROUP 00, How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).

	Replace combination meter and go to Step 6.

STEP 6. Check whether the diagnosis code is reset.

Recheck if the diagnosis code is set.

(1)Erase the diagnosis code.

(2)Turn the ignition switch to "ON" position.

(3)Check if the diagnosis code is set.

Q. Is the check result satisfactory?

	The procedure is complete.

	Go to Step 1.