DTC C1202/68: Master Reservoir Level Malfunction [08/2013 - ]: Procedure

1. Check that the brake fluid level is sufficient.

   OK

   Brake fluid level is sufficient.

   HINT: 

   If the fluid level is low, check for fluid leaks, and repair as necessary.

   1. Check for brake fluid leaks (Connection between the brake booster pump assembly, brake master cylinder reservoir assembly and brake booster with master cylinder assembly, and the brake booster with master cylinder assembly and wheel cylinders).

      HINT: 

      If no leaks exist, add and adjust fluid using the Techstream. Refer to ON-VEHICLE INSPECTION [08/2013 - ] .

   2. Check that the DTC is not output again. Refer to DTC CHECK / CLEAR [08/2013 - ] .
2. Check that there are no leaks from the connections between the brake booster pump assembly and brake booster with master cylinder assembly.

   HINT: 

   As a visual check is very difficult, perform the check with the following procedure.

   1. Bleed the air from the brake system. Refer to BLEEDING [08/2013 - ] .
   2. Connect the Techstream to the DLC3.
   3. Turn the power switch on (IG).
   4. Select the Data List on the Techstream. Refer to DATA LIST / ACTIVE TEST [08/2013 - ] .
      ABS/VSC/TRAC
      
      

      Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
      Accumulator Sensor	Accumulator pressure sensor / Min.: 0.00 V, Max.: 5.00 V	Specified value: 2.90 to 4.20 V	When brake fluid is stored in the accumulator: Accumulator pressure changes in accordance with volume of fluid stored in the accumulator

   5. Wait for 30 seconds without depressing the brake pedal.
   6. Check that the accumulator pressure sensor output value change is within the specified range.

      OK

      Accumulator pressure sensor output value change is less than 0.55 V.

NG → CHECK AND REPAIR BRAKE FLUID LEAKS OR ADD FLUID 

OK: Go to next step 

1. Turn the power switch off.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

2. Remove the reservoir filler cap.
3. Make sure that there is no looseness at the locking part and the connecting part of the connector.
4. Disconnect the A26 brake fluid level warning switch (brake master cylinder reservoir assembly) connector.
5. Measure the resistance according to the value(s) in the table below.

   HINT: 

   A float is located inside the reservoir. Its position changes according to the level of brake fluid.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   2 (LBL) - 1 (GND)	Brake fluid level warning switch OFF (Float up)	1.84 to 2.16 kΩ
   2 (LBL) - 1 (GND)	Brake fluid level warning switch ON (Float down)	Below 1 Ω

   TEXT IN ILLUSTRATION
   
   

   *a	Component without harness connected (Brake Fluid Level Warning Switch (Brake Master Cylinder Reservoir Assembly))

NG → See step   7 

OK: Go to next step 

1. Make sure that there is no looseness at the locking part and the connecting part of the connector.
2. Disconnect the A24 skid control ECU (brake booster with master cylinder assembly) connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   A24-36 (LBL) - A26-2 (LBL)	Always	Below 1 Ω
   A24-36 (LBL) - Body ground	Always	10 kΩ or higher
   A26-1 (GND) - Body ground	Always	Below 1 Ω

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Reconnect the A24 skid control ECU (brake booster with master cylinder assembly) connector.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

2. Turn the power switch on (IG).
3. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   A26-2 (LBL) - Body ground	Power switch on (IG)	4 to 7 V

   TEXT IN ILLUSTRATION
   
   

   *a	Front view of wire harness connector (to Brake Fluid Level Warning Switch (Brake Master Cylinder Reservoir Assembly))

NG → See step   8 

OK: Go to next step 

1. Turn the power switch off.
2. Reconnect the A26 brake fluid level warning switch (brake master cylinder reservoir assembly) connector.
3. Disconnect the A34 brake pedal stroke sensor assembly connector.
4. Perform a road test according to Freeze Frame Data or customer problem analysis. While driving, check for abnormal brake pedal vibration caused by brake discs that are worn or have excess runout.

   OK

   Brake pedal does not vibrate during braking.

   HINT: 

   • An unevenly worn disc may vibrate the caliper pistons and cause fluctuations in brake line pressure, triggering a malfunction detection condition.
   • The brake pedal does not kick back due to caliper piston vibration during electronically controlled brake system control.
   • If the brake pedal stroke sensor assembly connector is disconnected, the fail-safe function will prohibit electronically controlled brake system control.
   • The Active Test does not prohibit electronically controlled brake system control when the vehicle is being driven, so disconnect the brake pedal stroke sensor assembly connector before continuing with inspection.
   • Uneven disc wear can be checked by measuring the disc thickness variation. Refer to INSPECTION [08/2013 - ] for front or refer to INSPECTION [08/2013 - ] for rear).

NG → REPLACE BRAKE DISC 

OK: Go to next step 

1. Reconnect the A34 brake pedal stroke sensor assembly connector.
2. Clear the DTCs. Refer to DTC CHECK / CLEAR [08/2013 - ] .
3. Turn the power switch on (READY).
4. Perform a road test.
5. Check if the same DTC is output. Refer to DTC CHECK / CLEAR [08/2013 - ] .

   Result

   Result	Proceed to
   DTC C1202/68 is not output.	A
   DTC C1202/68 is output.	B

   HINT: 

   If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step. Refer to PROBLEM SYMPTOMS TABLE [08/2013 - ] .

B → See step   8 

A → See step   9