Inspection Procedure 8

Inspection Procedure 8: Seat belt reminder function does not work normally.

CAUTION:
Whenever the ECU is replaced, ensure that the input and output signal circuits are normal.

















TECHNICAL DESCRIPTION (COMMENT)

If the seat belt reminder function does not work normally, the seat belt switch input circuit, the combination meter or center panel unit may be defective.

TROUBLESHOOTING HINTS

- The seat belt switch (driver's side) may be defective.
- The seat belt switch (passenger's side) may be defective.
- The combination meter may be defective.
- The center panel unit 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
- MB992006: Extra Fine Probe

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

(1)
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.

Connect scan tool MB991958. Refer to "How to connect the Scan Tool (M.U.T.-III) Reading and Clearing Diagnostic Trouble Codes."

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

(3)Diagnose the CAN bus line.

(4)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is the CAN bus line found to be normal?

YES Go to Step 2.
NO Repair the CAN bus line CAN Bus Diagnostics Chart).
STEP 2. Using scan tool MB991958, read for SRS diagnostic trouble code.

Check the DTC is set to the SRS.

Q. Is the DTC set?

YES Troubleshoot the SRS Supplemental Restraint System).
NO Go to Step 3.
STEP 3. Check seat belt switch (driver's side) connector D-33 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q. Is seat belt switch (driver's side) connector D-33 in good condition?

YES Go to Step 4.
NO Repair the defective connector.
STEP 4. Check the seat belt switch.

Testing and Inspection.

Q. Is the check result normal?

YES Go to Step 5.
NO Replace the seat belt switch.
STEP 5. Check the ground circuit to the seat belt switch (driver's side). Test at seat belt switch (driver's side) connector D-33.

(1)Disconnect the connector, and measure at the wiring harness side.





(2)Measure the resistance value between terminal 1 and ground.

- The resistance should be 2 ohms or less.

Q. Is the measured resistance 2 ohms or less?

YES Go to Step 7.

NO Go to Step 6.

STEP 6. Check the wiring harness between seat belt switch (driver's side) connector D-33 (terminal 1) and ground.

Check the ground wire for open circuit.

Q. Is the wiring harness between seat belt switch (driver's side) connector D-33 (terminal 1) and ground in good condition?

YES The trouble can be an intermittent malfunction How to Cope With Intermittent Malfunctions).
NO Repair the wiring harness.
STEP 7. Check combination meter connector C-203 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q. Is combination meter connector C-203 in good condition?

YES Go to Step 8.
NO Repair the defective connector.
STEP 8. Check the wiring harness between combination meter connector C-203 (terminal 5) and seat belt switch [driver's side] connector D-33 (terminal 2).

- Check the input line for open and short circuit.

NOTE:
Also check intermediate connector C-26 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connector C-26 is damaged, repair or replace the damaged component(s) as described in Harness Connector Inspection Harness Connector Inspection.

Q. Is the wiring harness between combination meter connector C-203 (terminal 5) and seat belt switch[ driver's side] connector D-33 (terminal 2) in good condition?

YES Go to Step 9.
NO Repair the wiring harness.
STEP 9. Check center panel unit connector C-205 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q. Is center panel unit connector C-205 in good condition?

YES Go to Step 10.
NO Repair the defective connector.
STEP 10. Check the wiring harness between combination meter connector C-203 (terminal 19) and center panel unit connector C-205 (terminal 16).

- Check the input line for open and short circuit.

Q. Is the wiring harness between combination meter connector C-203 (terminal 19) and center panel unit connector C-205 (terminal 16) in good condition?

YES Go to Step 11.
NO Repair the wiring harness.
STEP 11. Retest the system.

The seat belt reminder function should work normally.

Q. Is the check result normal?

YES [The seat belt reminder function works normally.] : The trouble can be an intermittent malfunction How to Cope With Intermittent Malfunctions).
NO [Tone alarm sounds do not sound.] : Replace the combination meter.
NO [The indicator (driver's side) does not illuminate.] : Replace the combination meter.
NO [The indicator (passenger's side) does not illuminate.] : Replace the center panel unit.