Inspection Procedure 3: When the Parking Brake Lever Is Released, the Brake Warning Light Does Not Turn Off

INSPECTION PROCEDURE 3: When the Parking Brake Lever is Released, the Brake Warning Light does not Turn Off.














TECHNICAL DESCRIPTION (COMMENT)
^ The parking brake switch turns on and off by operating the parking brake lever, and the brake warning light illuminates and goes out, indicating the operating status of parking brake to a driver.
^ The brake fluid level switch is installed to the master cylinder and the switch turns on when the brake fluid reach the lower level. Therefore, the brake warning light illuminates to indicate the status to the driver.

TROUBLESHOOTING HINTS (THE MOST LIKELY CAUSES FOR THIS CASE:)
^ Damaged wiring harness or connector
^ Brake fluid level switch defective
^ Parking brake switch defective
^ Combination meter defective

DIAGNOSIS

Required Special Tools:
^ MB991958: Scan Tool (M.U.T.-III Sub Assembly)
^ MB991824: V.C.I.
^ MB991827: M.U.T.-III USB Cable
^ MB991910: M.U.T.-III Main Harness A

STEP 1. Check the brake fluid level.
Q: Is the brake fluid level within between the lower level and upper level?
YES: Go to Step 2.
NO: Check if the brake pad is worn. If not, replenish the brake fluid. Then go to Step 9.

STEP 2. Using scan tool MB991958, check actuator test.

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.

1) Connect scan tool MB991958 to the data link connector.
2) Turn the ignition switch to the "ON" position.
3) Turn the parking brake switch and brake fluid level switch to "OFF" position.
4) Set scan tool MB991958 to the actuator test mode.
^ Item 20: Indicator light 1: ON
^ The brake warning light illuminates.
^ Item 21: Indicator light 1: OFF
^ The brake warning light goes out.
5) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the check result normal?
YES: Go to Step 3.
NO: Replace the combination meter.

STEP 3. Check the parking brake switch.
Refer to Testing and Inspection.
Q: Is the parking brake switch normal?
YES: Go to Step 4.
NO: Replace the parking brake switch. then go to Step 9.

STEP 4. Check the brake fluid level switch.
Refer to Brake Fluid Level Switch Check Testing and Inspection.
Q: Is the parking brake fluid level switch normal?
YES: Go to Step 5.
NO: Replace the brake fluid level switch. Then go to Step 9.

STEP 5. Check parking brake switch connector C-16, brake fluid level switch connector A-04, intermediate connector C-24 and combination meter connector C-04 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 6.
NO: Repair or replace the faulty connector. Then go to Step 9.








STEP 6. Check the harness wire parking brake switch connector C-16 terminal 1 and combination meter connector C-04 terminal 9 for damage.







Q: Are the harness wires in good condition?
YES: Go to Step 7.
NO: Repair the damaged harness wire. Then go to Step 9.

STEP 7. Check the harness wire brake fluid level switch connector A-04 terminal 1 and combination meter connector C-04 terminal 9 for damage.




Q: Are there harness wires in good condition?
YES: Go to Step 8.
NO: Repair the damaged harness wire. Then go to Step 9.





STEP 8. Retest the system
Q: Does the brake warning light turn off when the parking brake lever is release?
YES: It can be assumed that this malfunction is intermittent.
NO: Replace the combination meter.

STEP 9. Retest the system
Q: Does the brake warning light turn off when the parking brake lever is released?
YES: The procedure is complete.
NO: Return to Step 1.