INSPECTION PROCEDURE 2: When the Parking Brake Lever is Pulled, the Brake Warning Light does not Illuminate: 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

1. 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 (Refer to COMBINATION METER ASSEMBLY ).
2. STEP 2. Check the parking brake switch. 

   Refer to PARKING BRAKE SWITCH CHECK  .

   Q: Is the parking brake switch normal? 

   • YES:  Go to Step 3.
   • NO:  Replace the parking brake switch (Refer to PARKING BRAKE SWITCH CHECK  ). Then go to  Step 6.
3. STEP 3. Connector check: C-117 parking brake switch connector, C-21 intermediate connector < Turbo > or C-22 intermediate connector < Non-turbo > and C-04 combination meter connector 

   Q: Is the check result normal? 

   • YES:  Go to Step 4.
   • NO:  Repair or replace the faulty connector (Refer to HARNESS CONNECTOR INSPECTION ). Then go to  Step 6.
4. STEP 4. Check the wiring harness for an open circuit between C-117 parking brake switch connector terminal No. 1 and C-04 combination meter connector terminal No. 4. 
   1. Disconnect C-117 parking brake switch connector form C-04 combination meter connector, and measure at the wiring harness side connector.
   2. Measure the resistance between C-117 parking brake switch connector terminal No. 1 and C-04 combination meter connector terminal No. 4.

      OK: Continuity exists (2 Ω 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-117 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.
5. 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 (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTION ).
   • NO:  Replace the combination meter (Refer to COMBINATION METER ASSEMBLY ).
6. 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.