Inspection Procedure 2

Inspection Procedure 2: The TPMS Warning Light Flash for About 1 Minute and Then Remain Illuminated.













CIRCUIT OPERATION

- The TPMS warning light will flash for about 1 minute and then remain illuminated when a fault has occurred in the TPMS.
- The TPMS warning light may also flash for about 1 minute and then remain illuminated when a fault has occurred in the TPMS warning light signal circuit (including open circuit and shorted circuit).

TECHNICAL DESCRIPTION (COMMENT)

- If any TPMS DTCs are set, carry out the relevant troubleshooting.
- If no TPMS DTC is set, carry out the troubleshooting for the TPMS warning light signal circuit.

TROUBLESHOOTING HINTS (THE MOST LIKELY CAUSES FOR THIS CASE:)

- A fault has occurred in the TPMS.
- Damaged harness wire or connector in the TPMS warning light signal circuit
- Malfunction of the combination meter
- Malfunction of the TPMS receiver

DIAGNOSIS

Required Special Tools:

- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: Vehicle Communication Interface (V.C.I.)
- MB991827: M.U.T.-III USB Cable
- MB991910: M.U.T.-III Main Harness A

STEP 1. Using scan tool MB991958, read the diagnostic trouble code.





(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 to the data link connector.
(2)Turn the ignition switch to the "ON" position.
(3)Check whether any TPMS DTC is set.

Q. Is any TPMS DTC set?

YES Carry out the relevant TPMS troubleshooting (Refer to Tire Pressure Monitoring System (TPMS)).

NO Go to Step 2.

STEP 2. Check TPMS receiver connector C-121 and combination meter connector C-04 for loose, corroded or damaged terminals, or terminals pushed back in the connector.









Q. Are TPMS receiver connector C-121 and combination meter connector C-04 in good condition?

YES Go to Step 3.

NO Repair it. Then go to Step 5.

STEP 3. Check the wiring harness between TPMS receiver connector C-121 (terminal 1 and 2) and combination meter connector C-04 (terminal 3 and 4).













NOTE:
Also check joint connector (3) C-03 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If joint connector (3) C-03 is damaged, repair or replace the connector as described in Harness Connector Inspection Harness Connector Inspection.

Q. Are the wiring harness between TPMS receiver connector C-121 (terminal 1 and 2) and combination meter connector C-04 (terminal 3 and 4) in good condition?

YES Go to Step 4.

NO Repair or replace it. Then go to Step 5.

STEP 4. Check the combination meter.

Check that the combination meter warning lights and indicators other than TPMS warning light illuminate normally.

Q. Are there any faults on the combination meter?

YES Replace the combination meter assembly (Refer to Overhaul). Then go to Step 5.
NO Replace the TPMS receiver (Refer to TPMS Receiver Removal and Installation) and execute "Tire Pressure Sensor ID Registration" on scan tool MB991958 "Special Function" (Refer to Tire Pressure Sensor ID Registration). Then go to Step 5.
STEP 5. Retest the system.

Q. Turn the ignition switch to the "ON" position. Does the TPMS warning light illuminate for three seconds, and then go out?

YES The procedure is complete.
NO Repeat the troubleshooting from Step 1.