Inspection Procedure A-1

Communication with the SWS Monitor Kit is not possible.

Scan Tool Communication And ETACS-ECU Ground Circuit:

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

TROUBLESHOOTING HINTS
- The SWS monitor body (I/F cartridge) may be defective
- The SWS monitor harness may be defective
- The ETACS-ECU may be defective
- The wiring harness or connectors may have loose, corroded, or damaged terminals, or terminals pushed back in the connector

DIAGNOSIS

Required Special Tools:
- MB991223: Harness Set
- MB991958: Scan Tool (MUT-III Sub Assembly)
- MB991824: Vehicles communication interface (V.C.I.)
- 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. Verify SWS monitor kit MB991813 for proper connection.

Q: Is SWS monitor kit MB991813 connected with the column switch properly?

YES: Go to Step 2.

NO: Connect SWS monitor kit MB991813 to the column switch securely.

STEP 2. Verify 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 not possible."




STEP 3. Check ETACS-ECU connector C-118 and C-119 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

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

YES: Go to Step 4.

NO: Repair or replace the damaged component(s). Refer to Harness Connector Inspection. The system should communicate with the SWS monitor normally.

STEP 4. Check the ground circuit to the ETACS-ECU. Measure the resistance at ETACS-ECU connectors C-118 and C-119.







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




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

Q: Is the measured resistance 2 ohms or less?

YES: Go to Step 6.

NO: Go to Step 5.







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 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If junction block connector C-108 is damaged, repair or replace the damaged component(s) as described in Harness Connector Inspection.

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

YES: No action is necessary and testing is complete.

NO: The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary. The system should communicate with the SWS monitor kit normally.




STEP 6. Check data link connector C-29 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q: Is data link connector C-29 in good condition?

YES: Go to Step 7.

NO: Repair or replace the damaged component(s). 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 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If joint connector C-77 is damaged, repair or replace the damaged component(s) 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: The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary. The system should communicate with the SWS monitor kit normally.