U1117

DTC U1117: IMMOBILIZER-ECU TIME-OUT

CAUTION
- If the ECM or the PCM output the DTC U1117, make sure to diagnose the CAN bus line.
- Before replacing the ECU, make sure that the communication circuit is operating normally.

DTC SET CONDITIONS

Check Condition
- Ignition switch is in ON position.

Judgement Criterion
- Unable to receive ETACS-ECU (immobilizer-ECU) signals through the CAN bus line.

COMMENT

Current Trouble
- Some of the possible causes are a harness or connector damage between the ECM or the PCM and the ETACS-ECU (immobilizer-ECU) on the CAN bus line, a failure in the ETACS-ECU (immobilizer-ECU) power supply system, a failure in the ETACS-ECU (immobilizer-ECU), or a failure in the ECM or the PCM .

Past Trouble
- Proceed to troubleshoot based on a harness or connector damage on the CAN bus line between the ECM or the PCM and ETACS-ECU (immobilizer-ECU), and a failure in the ETACS-ECU (immobilizer-ECU) power supply system. Refer to "How to cope with past trouble".

CAUTION: When the ignition key is maintained within the range "A" (i.e., the ignition switch IG2 is in OFF position but the cranking does not start) for more than 1 second, ECM or PCM stores DTC U1117 (the past trouble).

NOTE: If a malfunction occurred in the past, a failure cannot be discovered through the MB991958 CAN bus diagnosis even if there might be a problem with the CAN bus. In this case, Furthermore, it is possible to narrow down the areas of the possible failures from the DTCs that are output by the ECUs, which are communicating on the CAN bus (Refer to Can bus Diagnostics Flow in Information Bus).

TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
- CAN line harness damage or connector damage.
- ETACS-ECU (immobilizer-ECU) failed.
- ECM failed.
- PCM failed.

DIAGNOSIS

Required Special Tools:
- MB991958: Scan tool (MUT-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: USB Cable
- MB991910: Main Harness A

STEP 1. Using scan tool MB991958, diagnose CAN bus line.

CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.

1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Diagnose CAN bus line.
4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the CAN bus line normal?

YES: Go to Step 2.

NO: Repair the CAN bus line. Refer to Can bus Diagnostics Table in Information Bus. Then go to Step 3.

STEP 2. Using scan tool MB991958, read the diagnostic trouble code (DTC).

1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Read the immobilizer-DTC.
4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the immobilizer-DTC set?

YES: Refer to Chassis Electrical, Immobilizer System - Diagnostic Trouble Code Chart.

NO: Go to Step 3.

STEP 3. Using scan tool MB991958, read the diagnostic trouble code (DTC).

1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. After the MFI-DTC has been deleted, read the MFI-DTC again.
4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is DTC U1117 set?

YES: Replace the ECM or the PCM. When the ECM or the PCM is replaced, register the encrypted code. Refer to Encrypted Code Registration Criteria Table in Antitheft and Alarm Systems.

NO: It can be assumed that this malfunction is intermittent of CAN bus line between ECM or PCM and ETACS-ECU (immobilizer-ECU).