Code No.U1100 Engine-ECU <M/T> or Engine-A/T-ECU <A/T> Time-out (Related to Engine) <3000, 3200 and 3800>

caution

If diagnosis code U1100 is set in the combination meter, always diagnose the CAN bus lines.
Whenever the ECU is replaced, ensure that the communication circuit is normal.

TROUBLE JUDGMENT

The combination meter receives engine control system-related signals from the engine-ECU <M/T> or engine-A/T-ECU <A/T> via CAN bus lines. If the display unit cannot receives the necessary signals, diagnosis code U1100 will be set.

note

For 2800-vehicles, diagnosis code No.U1101 does not mean that there is a problem.

COMMENTS ON TROUBLE SYMPTOM

Current trouble

Connector(s) or wiring harness in the CAN bus lines between the engine-ECU <M/T> or engine-A/T-ECU <A/T> and the combination meter, the power supply system to the engine-ECU <M/T> or engine-A/T-ECU <A/T>, the engine-ECU <M/T> or engine-A/T-ECU <A/T> 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 engine-ECU <M/T> or engine-A/T-ECU <A/T> and the combination meter, and the power supply system to the engine-ECU <M/T> or engine-A/T-ECU <A/T>. 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

. 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 54D - CAN Bus Line Diagnostic Flow

PROBABLE CAUSES

Damaged harness wires and connectors
Malfunction of engine-ECU <M/T> or engine-A/T-ECU <A/T>
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 normal?

Go to Step 2.

Repair the CAN bus lines. (Refer to GROUP 54D - Troubleshooting

). Repair the CAN bus line and go to Step 6.

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

Check whether the MPI system or Diesel system, and the A/T system diagnosis codes are set or not.

Q. Is the diagnosis code set?

Diagnose the MPI system or Diesel system, or the A/T system (Refer to GROUP 13A, Troubleshooting

<3000>, GROUP 13B, Troubleshooting

<3800>, GROUP 13D, Troubleshooting

<3200> or GROUP 23A, Troubleshooting

<A/T system>).

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.

Code No.U1100: engine-ECU <M/T> or engine-A/T-ECU <A/T> time-out (related to Engine)

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)On completion, check that the diagnosis code is not reset.

Q. Is the check result normal?

A poor connection, open circuit or other intermittent malfunction is present in the CAN bus lines between the engine-ECU <M/T> or engine-A/T-ECU <A/T> and the combination meter (Refer to GROUP 00 - How to use troubleshooting/Inspection Service Points

Replace engine-ECU <M/T> or engine-A/T-ECU <A/T> 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)On completion, check that the diagnosis code is not reset.

Q. Is the check result normal?

Replace combination meter and then 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)On completion, check that the diagnosis code is not reset.

Q. Is the check result normal?

The procedure is complete.

Go to Step 1.