Inspection Procedure 2: When the Parking Brake Lever Is Pulled, the Brake Warning Light Does Not Illuminate.
INSPECTION PROCEDURE 2: When the Parking Brake Lever is Pulled, the Brake Warning Light does not Illuminate.
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.
TROUBLESHOOTING HINTS (THE MOST LIKELY CAUSES FOR THIS CASE:)
^ Damaged wiring harness or connector
^ Parking brake switch defective
^ Combination meter defective
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, check combination meter 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 13: Indicator 4: ON
^ The brake warning light illuminates.
^ Item 13: Indicator 4: 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 2.
NO: Replace the combination meter.
STEP 2. Check the parking brake switch.
Q: Is the parking brake switch normal?
YES: Go to Step 3.
NO: Replace the parking brake switch. Then go to Step 6.
STEP 3. Connector check: C-122 parking brake switch connector, C-23 intermediate connector and C-04 combination meter connector
Q: Is the check result normal?
YES: Go to Step 4.
NO: Repair or replace the faulty connector. Then go to Step 6.
STEP 4. Check the wiring harness for an open circuit between C-122 parking brake switch connector terminal No.1 and C-04 combination meter connector terminal No.4.
1) Disconnect C-122 parking brake switch connector from C-04 combination meter connector, and measure at the wiring harness side connector.
2) Measure the resistance between C-122 parking brake switch connector terminal No.1 and C-04 combination meter connector terminal No.4.
OK: Continuity exists (2 ohms or less)
Q: Is the check result normal?
YES: Go to Step 5.
NO: A open circuit may be present in the wiring harness between C-122 parking brake switch connector terminal No.1 and C-04 combination meter connector terminal No.4. Repair the wiring harness if necessary, and then go to Step 6.
STEP 5. Retest the system.
Q: Does the brake warning light illuminate when the parking brake lever is pull?
YES: It can be assumed that this malfunction is intermittent.
NO: Replace the combination meter.
STEP 6. Retest the system.
Q: Does the brake warning light illuminate when the parking brake lever is pulled?
YES: The procedure is complete.
NO: Return to Step 1.