Inspection Procedure A-1

Communication with the SWS Monitor Kit is Impossible.

Scan Tool Communication And ETACS-ECU Ground Circuit:

TECHNICAL DESCRIPTION (COMMENT)
The SWS monitor kit may be connected improperly.

TROUBLESHOOTING HINTS
- Malfunction of the SWS monitor body (I/F cartridge)
- Malfunction of the SWS monitor harness
- Malfunction of the ETACS-ECU
- Damaged harness wires or connectors

DIAGNOSIS

Required Special Tools:
- MB991223: Harness Set
- MB991958: Scan Tool (MUT-III Sub Assembly)
- MB991824: Vehicles communication interface
- MB991827: MUT-III USB cable
- MB991911: MUT-III Main harness B
- MB991813: SWS monitor kit
- MB991806: SWS monitor cartridge
- MB991812: SWS monitor harness (for column-ECU)
- MB991922: Probe harness

STEP 1. Check SWS monitor kit MB991862 for proper connection.

Q: Is SWS monitor kit MB991862 connected with the column switch properly?

YES: Go to Step 2.

NO: Connect SWS monitor kit MB991862 to the column switch securely.

STEP 2. Check the power supply circuit to the ETACS-ECU.

Q: Does the system communicate with scan tool MB991958 when the ignition switch is turned to the "ON" position?

YES: Go to Step 3.

NO: Refer to Inspection Procedure A-3 "Communication with the ETACS-ECU is impossible."

STEP 3. Measure at ETACS-ECU connector C-118 and C-119 in order to check the ground circuit to the ETACS-ECU.




1. Disconnect ETACS-ECU connector C-118, C-119, and measure at the junction block side.







2. Measure the resistance value between terminal 56, 3 and ground.
- The measured value should be 2 ohm or less.

Q: Does the measured resistance value correspond with this range?

YES: Go to Step 6.

NO: Go to Step 4.




STEP 4. Check ETACS-ECU connector C-118 and C-119 for damage.

Q: Is ETACS-ECU connector C-118 and C-119 in good condition?

YES: Go to Step 5.

NO: Repair or replace the connector. Refer to Harness Connector Inspection. The system should communicate with the SWS monitor normally.







STEP 5. Check the wiring harness between ETACS-ECU connector C-119 (terminal 3) or ETACS-ECU connector C-118 (terminal 56) and the ground.

NOTE: Also check junction block connector C-108. If junction block connector C-108 is damaged, repair or replace the connector as described in Harness Connector Inspection.

Q: Is the wiring harness between ETACS-ECU connector C-119 (terminal 3) or ETACS-ECU connector C-118 (terminal 59) and the ground in good condition?

YES: No action to be taken.

NO: Repair the wiring harness. The system should communicate with the SWS monitor kit normally.







STEP 6. Check ETACS-ECU connector C-118 and data link connector C-29 for damage.

Q: Are ETACS-ECU connector C-118 and data link connector C-29 in good condition?

YES: Go to Step 7.

NO: Repair or replace the connector. Refer to Harness Connector Inspection. The system should communicate with the SWS monitor kit normally.










STEP 7. Check the wiring harness between ETACS-ECU connector C-118 (terminals 51 and 67) and data link connector C-29 (terminals 9 and 1).

NOTE: Also check joint connector C-77. If joint connector C-77 is damaged, repair or replace the connector as described in Harness Connector Inspection.

Q: Is the wiring harness between ETACS-ECU connector C-118 (terminals 51 and 67) and data link connector C-29 (terminals 9 and 1) in good condition?

YES: Replace the ETACS-ECU. The system should communicate with the SWS monitor kit normally.

NO: Repair the wiring harness. The system should communicate with the SWS monitor kit normally.