Inspection Procedure 3: the TPMS Warning Light Does Not Illuminate As A Bulb Check For Three Seconds When the Ignition Switch

INSPECTION PROCEDURE 3: The TPMS Warning Light does not Illuminate as a Bulb Check for Three Seconds when the Ignition Switch is Turned to the "ON" Position.

TPMS Receiver Power Supply And Ground, Ignition Signal Input And TPMS Warning Light Circuit:

CIRCUIT OPERATION
For three seconds after the ignition switch is turned to the "ON" position, the TPMS receiver illuminates the TPMS warning light to check any breaks in the TPMS warning light circuit.

TECHNICAL DESCRIPTION (COMMENT)
If the TPMS warning light does not illuminate for three seconds when the ignition switch is turned to the "ON" position, diagnose the TPMS warning light signal circuit, power supply to the TPMS receiver, ignition signal, and/or ground circuit.

TROUBLESHOOTING HINTS (THE MOST LIKELY CAUSES FOR THIS CASE:)
^ TPMS warning light signal harness wire open circuit
^ Ignition signal harness wire of the TPMS receiver or battery power supply harness wire open circuit
^ Ground harness wire of the TPMS receiver open circuit
^ Malfunction of the combination meter
^ Malfunction of the TPMS receiver

DIAGNOSIS

Required Special Tool:
^ MB991223: Harness Set

STEP 1. Measure the voltage at C-133 TPMS receiver connector.





1. Disconnect TPMS receiver connector C-133, and check at the harness connector (component side).





2. Measure the voltage between terminal 5 and ground. It should measure battery positive voltage (approximately 12 volts).
3. Turn the ignition switch to the "ON" position.





4. Measure the voltage between terminal 10 and ground. It should measure battery positive voltage (approximately 12 volts).
Q: Is battery positive voltage (approximately 12 volts) present?
YES [all the measured voltages are equivalent to battery positive voltage] : Go to Step 6.
NO [voltage between terminal 5 and ground is not battery positive voltage] : Go to Step 2.
NO [voltage between terminal 10 and ground is not battery positive voltage] : Go to Step 4.

STEP 2. Check the following connectors.





^ Joint connector C-01





^ Intermediate connector C-29





^ TPMS receiver connector C-133
Check the connectors for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Are the connectors and terminals in good condition?
YES: Go to Step 3.
NO: Repair it. Then go to Step 11.

STEP 3. Check the following harness wire.








^ The wire between relay box in engine compartment (fuse number 22) and TPMS receiver connector C-133 (terminal 5)
Q: Is the harness wire damaged?
YES: Repair or replace it. Then go to Step 11.
NO: Repeat the troubleshooting from Step 1.

STEP 4. Check the following connectors.








^ Junction block connectors C-211 and C-215





^ Joint connector C-102





^ TPMS receiver connector C-133
Check the connectors for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Are the connectors and terminals in good condition?
YES: Go to Step 5.
NO: Repair it. Then go to Step 11.

STEP 5. Check the following harness wire.








^ The wire between junction block connector C-215 (terminal 6) and TPMS receiver connector C-133 (terminal 10)
Q: Is the harness wire damaged?
YES: Repair or replace it. Then go to Step 11.
NO: Repeat the troubleshooting from Step 1.

STEP 6. Measure the resistance at C-133 TPMS receiver connector.





1. Disconnect TPMS receiver connector C-133, and check at the harness side.





2. Measure the resistance between terminal 6 and ground. It should measure less than 2 ohms.
Q: Is the measured resistance less than 2 ohms?
YES: Go to Step 8.
NO: Go to Step 7.

STEP 7. Check the following connectors.





^ Joint connector C-03





^ TPMS receiver connector C-133
Check the connectors for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Are the connectors and terminals in good condition?
YES: Go to Step 8.
NO: Repair it. Then go to Step 12.

STEP 8. Check the following harness wire.








^ The wire between TPMS receiver connector C-133 (terminal 6) and ground (No.8).
Q: Is the harness wire damaged?
YES: Repair or replace it. Then go to Step 11.
NO: Return to Step 6.

STEP 9. Check the TPMS warning light circuit at TPMS receiver connector C-133.





1. Disconnect TPMS receiver connector C-133.
2. Turn the ignition switch to the "ON" position.





3. Ground terminal 7 of disconnected connector C-133 from the TPMS receiver. The TPMS warning light should illuminate.
Q: Does the TPMS warning light illuminate?
YES: Replace the TPMS receiver and execute "Tire Pressure Sensor ID Registration" on scan tool MB991958 "Special Function". Then go to Step 11.
NO: Go to Step 9.

STEP 10. Check the following connectors.





^ Combination meter connector C-101





^ TPMS receiver connector C-133 Check the connectors for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Are the connectors and terminals in good condition?
YES: Go to Step 10.
NO: Repair it. Then go to Step 11.

STEP 11. Check the following harness wire.








^ The wire between combination meter connector C-101 (terminal 20) and TPMS receiver connector C-133 (terminal 7)
Q: Is the harness wire damaged?
YES: Repair or replace it. Then go to Step 11.
NO: Replace the meter assembly. Then go to Step 11.

STEP 12. 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.