Symptom Troubleshooting [Abs]: Other Mazda 3 BM

FOREWORD [ABS]

1. If there is any vehicle malfunction complaint lodged by a customer, perform malfunction diagnosis according to the «TROUBLESHOOTING PROCEDURE»(ref-579492-S12543027152013100700000) .

Troubleshooting Procedure Flow Chart. Scheme 59

Scheme 60

Scheme 61

1. If the malfunction does not recur, verify the malfunction cause by performing the following actions: Based on the repair order form, attempt to drive the vehicle or perform tests to replicate the malfunction, record the data (such as CAN circuit voltage) at that time, and detect the malfunction cause. Refer to [Determining Open Circuit Location] based on the recorded DTC, shake the wiring harness or connector of the electrical component which is suspected to be the cause of the malfunction, and inspect for any changes in CAN system voltage or occurrence of any DTCs. (Scheme 60): Shaking Wiring Harness Or Connector Of Electrical Component Inspect the female terminals on the connector of the electric component which is suspected to be the cause of the malfunction for poor connection. (Scheme 61): Inspecting Electric Component Connector Female Terminals

PRECAUTION [ABS]

1. Any one or a combination of the ABS warning and brake system warning lights illuminates even when the system is normal. Warning lights that may illuminate and/or flash Cases in which the light may illuminate Conditions in which the light will go out ABS, EBD control Either or both of the following lights illuminate: ABS warning light Brake system warning light *1 When the front wheels are jacked up, stuck, or placed on a chassis roller, and only the front wheel ABS wheel-speed sensors are spun. After turning off the ignition once and then restarting the engine, the vehicle is driven at 10km/h {6.2 mph} or more , and then normal operation is verified. ABS: Cuts control EBD: Cuts control, in cases where the light may illuminate, only when ABS CM detects that a wheel-speed sensor determines that more than two wheels are malfunctioning. Operates control, if wheel-speed sensor determines that more than three wheels are functioning correctly. Parking brake is not fully released while driving. Brake drag. Sudden acceleration/deceleration. Left/right or front/rear tires are different. (Size, radius, tire pressure, or wear is other than that listed on tire label.) Both of the following lights illuminate: ABS warning light Brake system warning light Battery voltage at ABS HU/CM ignition terminal N drops below approx. 8 V. *2 Battery voltage rises above approx. 8 V. ABS: Cuts control EBD: Cuts control Brake system warning light Brake switch signal error (stuck at on/off) Normal operation of brake switch signal is verified ABS: Operates control EBD: Operates control Brake fluid amount is low. Brake fluid level lower than recommended amount. *1 In cases where the light may illuminate, only when ABS HU/CM detects that a wheel-speed sensor determines that more than two wheels are malfunctioning. *2 If battery voltage drops below 8 V while vehicle speed is greater than 20 km/h {12.4 mph}, ABS HU/CM records DTC U3003:16.
2. Precautions during servicing of ABS The ABS is composed of electrical and mechanical parts. It is necessary to categorize malfunctions as being either electrical or hydraulic when performing troubleshooting. Malfunctions in electrical system The ABS hydraulic unit and control module (ABS HU/CM) has an on-board diagnostic function. With this function, the ABS warning light and/or brake system warning light will illuminate when there is a problem in the electrical system. Also, past and present malfunctions are recorded in the ABS HU/CM. This function can find malfunctions that do not occur during periodic inspections. Connect the M-MDS to the DLC-2. The stored malfunctions will be displayed in the order of occurrence. To find out the causes of ABS malfunctions, use these on-board diagnostic results. If a malfunction occurred in the past but is now normal, the cause is likely a temporary poor connection of the wiring harness. The ABS HU/CM usually operates normally. Be careful when searching for the cause of malfunction. After repair, it is necessary to clear the DTC from the ABS HU/CM memory. Also, if the ABS related parts have been replaced, verify that no DTC has been displayed after repairs. After repairing the ABS wheel-speed sensor or ABS sensor rotor, or after replacing the ABS CM (ABS motor or ABS motor relay or solenoid valve), the ABS warning light may not go out * even when the ignition is switched to ON. In this case, drive the vehicle at a speed of 10 km/h {6.2 mph} or more , make sure that ABS warning light goes out, and then clear the DTC. * The brake system warning light also illuminates when any two wheels malfunction, or battery voltage drops below 8 V . When repairing, if the ABS related connectors are disconnected and the ignition is switched to ON, the ABS CM will mistakenly detect a fault and record it as a malfunction. To protect the ABS HU/CM, make sure the ignition is switched to off before connecting or disconnecting the ABS CM connector. Malfunctions in hydraulic system Symptoms in a hydraulic system malfunction are similar to those in a conventional brake malfunction. However, it is necessary to determine if the malfunction is in an ABS component or the conventional brake system. The ABS hydraulic unit contains delicate mechanical parts. If foreign material enters into the component, the ABS may fail to operate. Also, it will likely become extremely difficult to find the location of the malfunction in the event that the brakes operate but the ABS does not. Make sure foreign material does not enter when servicing the ABS (e.g. brake fluid replacement, pipe removal).

Malfunction data monitor method

1. Perform malfunction reappearance test according to malfunction reappearance mode and malfunction data monitor. The malfunction cause is found in the malfunction data.

Scheme 62

1. Inspect the connection condition of each female terminal.
2. Insert a male terminal to the female terminal and inspect the female terminal for looseness. (Scheme 62): Inspecting Female Terminals For Poor Connection

1. Verify the symptoms, and perform troubleshooting according to the appropriate number.

ABS Troubleshooting Chart. Scheme 63

NO.1 NEITHER ABS WARNING LIGHT NOR BRAKE SYSTEM WARNING LIGHT ILLUMINATE WITH SWITCH THE IGNITION TO ON [ABS]

NO.2 ABS WARNING LIGHT DOES NOT ILLUMINATE WITH SWITCH THE IGNITION TO ON [ABS]

NO.3 BRAKE SYSTEM WARNING LIGHT DOES NOT ILLUMINATE WITH SWITCH THE IGNITION TO ON [ABS]

NO.4 BOTH ABS WARNING LIGHT AND BRAKE SYSTEM WARNING LIGHT STAY ON 4 S OR MORE WITH SWITCH THE IGNITION TO ON [ABS]

NO.5 ABS WARNING LIGHT STAYS ON 4 S OR MORE WITH SWITCH THE IGNITION TO ON [ABS]

NO.6 BRAKE SYSTEM WARNING LIGHT STAYS ON 4 S OR MORE WITH SWITCH THE IGNITION TO ON (PARKING BRAKE IS RELEASED) [ABS]

NO.7 THERE IS MALFUNCTION IN THE SYSTEM EVEN THOUGH ABS WARNING LIGHT, BRAKE SYSTEM WARNING LIGHT, DO NOT ILLUMINATE [ABS]