Wheel Speed Sensor
All wheel speeds are detected by the Magnetic
Resistive Effect element type wheel speed sensor (1) and encoder (2). The wheel speed sensors are fixed to the steering knuckle and suspension knuckle.
The encoder consists of a permanent magnet which has south poles and north poles. As it is located on the wheel hub it turns along with the wheel.
The wheel speed sensor feeds pulse signals in proportion to the wheel speed to the ABS control module, which then calculates wheel speed based on such signal information.
Scheme 46
ABS (Antilock Brake System)
Refer to ABS DESCRIPTION .
EBD (Electronic Brake Force Distribution)
Refer to ABS DESCRIPTION .
Traction Control
This function controls the engine and brakes to prevent the driving wheels from spinning at the time of starting and accelerating. Particularly, this function is helpful for safe driving on muddy or icy roads. When ESP® hydraulic unit/control module assembly detects wheel spinning using information from the yaw rate/G sensor assembly and wheel speed sensors, it lowers the engine torque by reducing throttle position and retarding the ignition timing. At the same time, brake is applied to the spinning tire so that the engine torque can be transmitted to other tire.
Stability Control
This function maintains the vehicle stability by controlling the engine and brakes to prevent the vehicle from oversteering or understeering while turning.
When understeering occurs, this function lowers the engine torque and applies brake to the inner rear wheel to prevent the vehicle from moving outward. When oversteering occurs, this function applies brake to the outer front wheel to prevent the vehicle from moving inward.
ESP® system is equipped with ESP® OFF switch. Refer to "ESP® Off Switch" under ESP® COMPONENT LOCATION . Traction control function, stability control function and ESP® Cooperative Control under accelerative condition can be stopped and resumed by ESP® OFF switch or SUZUKI scan tool. However, traction control function, stability control function and μ-split control function under accelerative condition resume automatically when engine switch is pressed to change the ignition mode of keyless push start system to OFF and then to ON.
ESP® Cooperative Control
This function maintains the vehicle stability by assisting driver to turn steering with appropriate torque to prevent the vehicle from wheel shifting to one side on μ-split road.
μ -split road means a road whose friction coefficient is different between the points contacting with right wheels and the left wheels.
ESP® Hydraulic Unit/Control Module
The control module receives signals from each wheel speed sensor, ESP® OFF switch, brake master cylinder pressure sensor (7) and steering angle sensor. Based on these signals, the control module judges the vehicle conditions and controls the brake hydraulic pressure by combining the ON/OFF operation of the solenoid in the hydraulic unit and the pump motor operation.
The hydraulic unit contains an inlet solenoid valve (8) and an outlet solenoid valve (9) for each wheel as well as a cut solenoid valve (10) and a low pressure solenoid valve (11) for each hydraulic circuit. Also, a brake master cylinder pressure sensor, pump motor (6), etc. are included. The hydraulic pressure control is performed in 3 modes of pressure increase, pressure keeping and pressure reduction.
Scheme 47
- Pump motor: The pump motor turns on and applies pressure to each brake when braking is activated in the traction control and stability control state. When in the pressure reduction mode, it returns the brake fluid in the reservoir (12) to the master cylinder (1).
- Brake master cylinder pressure sensor: This sensor detects the brake hydraulic pressure in the primary piping when brake is applied in the normal condition. Also, it detects the pump motor driving state when brake is applied in the traction control and stability control state.
- Inlet solenoid valve: In the ABS, traction control and stability control state, this valve is activated in the pressure keeping and pressure reduction modes to close the fluid passage, thereby restricting increase of the hydraulic pressure applied to the brake caliper.
- Outlet solenoid valve: In the ABS, traction control and stability control state, this valve is activated in the pressure reduction mode to open the fluid passage, thereby lowering the hydraulic pressure in the brake caliper.
- Cut solenoid valve: When brake application is commanded in the traction control and stability control state, this valve is activated to close the fluid passage to apply the hydraulic pressure generated by the pump motor to the brake caliper.
- Low pressure solenoid valve: When brake application is commanded in the traction control and stability control state, this valve is activated to open the fluid passage from the master cylinder to the pump motor.
Steering Angle Sensor
The steering angle sensor is assembled with the contact coil as a unit and mounted to the steering column. Detecting the angle as the steering wheel is turned, it sends that information to the ESP® hydraulic unit/control module assembly.
ESP® OFF Switch
This switch is momentary contact type, and is located at the left of instrument panel, next to parking sensor OFF switch. When the ESP® OFF switch is pressed, the ESP® hydraulic unit/control module assembly stops the traction control function and stability control function. The ESP® OFF light in the combination meter lights and informs driver that these functions are inactive. When the ESP® OFF switch is pressed again, the ESP® hydraulic unit/control module assembly resumes these functions.
Refer to "wheel speed sensor" under ABS DESCRIPTION .
On-Board Diagnosis System Description
ESP® hydraulic unit/control module assembly is built in ESP® hydraulic unit/control module assembly and has the following functions.
Self-Diagnosis Function
ESP® hydraulic unit/control module assembly monitors each input and output signals. When ESP® hydraulic unit/control module assembly detects any malfunction, ABS warning light (1), EBD warning light (brake warning light) (2), ESP® warning light (3), and/or ESP® OFF light (4) are turned ON to indicate the abnormality to driver.
Scheme 48
- When ignition mode of the keyless push start system is changed to "ON", ABS warning light, EBD warning light (brake warning light), ESP® warning light and ESP® OFF light turn ON for 2 seconds to check its circuit.
- When no abnormality is detected (the system is in good condition), these lights turn OFF after 2 seconds. However, when parking brake is operated, EBD warning light (brake warning light) remains ON.
- When an abnormality in the system is detected, ABS warning light, EBD warning light (brake warning light), ESP® warning light and/or ESP® OFF light are turned ON and DTC is stored in ESP® hydraulic unit/control module assembly.
Fail-Safe Mode
If ESP® hydraulic unit/control module assembly stores a DTC, ESP® hydraulic unit/control module assembly stops ABS, EBD, traction control function and/or stability control function corresponding to the faulty area. It is possible to confirm the stopped function(s) by the warning/indicator lights in combination meter. See WARNING/INDICATOR LIGHT DESCRIPTION .
ESP® System Check
Refer to the following items for the details of each step.
| Step | Action | YES | NO |
|---|---|---|---|
| 1 | Malfunction analysis Perform CUSTOMER COMPLAINT ANALYSIS . Perform PROBLEM SYMPTOM CONFIRMATION . Perform DTC CHECK, RECORD AND CLEARANCE and recheck DTC. Is same DTC detected again after performing DTC clearance? | Go to Step 6. | Go to Step 2. |
| 2 | Visual Inspection Perform VISUAL INSPECTION . Is there any faulty condition? | Repair or replace malfunction part, and go to Step 6. | Go to Step 3. |
| 3 | Driving test Perform STEP 3: DRIVING TEST . Is malfunction detected? | Repair or replace malfunction part, and go to step 6. | Go to Step 4. |
| 4 | Brakes diagnosis Inspect and repair referring to BRAKE SYMPTOM DIAGNOSIS . Is malfunction detected? | Repair or replace malfunction part, and go to step 6. | Go to Step 5. |
| 5 | Intermittent problem check Check for intermittent troubles referring to INTERMITTENT CONNECTION AND POOR CONTACT INSPECTION . Is malfunction detected? | Repair or replace malfunction part, and go to step 6. | Go to Step 6. |
| 6 | Final confirmation test Perform STEP 6: FINAL CONFIRMATION TEST . Does trouble recur? | Go to Step 4. | End. |
DIAGNOSTICS PROCEDURE CHART
Customer Complaint Analysis
Record details of the problem (failure, complaint) and how it occurred as described by the customer. For this purpose, use of such a questionnaire form as shown in the following table will facilitate collecting information to the point required for proper analysis and diagnosis.
Scheme 49
Step 5: Intermittent Problem
Check parts where an intermittent trouble is easy to occur (e.g. wire harness, connector). Refer to INTERMITTENT CONNECTION AND POOR CONTACT INSPECTION and related circuit of trouble code recorded in STEP 1 to 5 .
EBD Warning Light (Brake Warning Light)
Note. Perform this check on a level place.
Scheme 50
- Check brake fluid level. See «BRAKE FLUID INSPECTION»(ref-585637-S41074719372013111200000) .
- Pull parking brake lever.
- Push engine switch to change ignition mode of keyless push start system to "ON".
- Check that EBD warning light (brake warning light) (1) comes ON. If EBD warning light (brake warning light) never light up, go to «EBD WARNING LIGHT (BRAKE WARNING LIGHT) DOES NOT COME ON AFTER PRESSING ENGINE SWITCH TO CHANGE IGNITION MODE TO "ON"»(ref-585576-S38351891382013111200000) .
- Release parking brake lever and check that EBD warning light goes OFF. If EBD warning light (brake warning light) remains ON and no DTC is stored in ABS control module, go to «EBD WARNING LIGHT (BRAKE WARNING LIGHT) COMES ON STEADY»(ref-585576-S13704591652013111200000) .
Scheme 51
- Confirm that ignition mode of keyless push start system is in "OFF".
- Connect SUZUKI scan tool to DLC (1). Special Tool SUZUKI scan tool (SUZUKI-SDT)
- Push engine switch to change ignition mode of keyless push start system to "ON".
- Read DTC according to instructions displayed on SUZUKI scan tool and prints it or write it down. Refer to SUZUKI scan tool operator's manual for further details. If communication between scan tool and ESP® control module is not possible, check that power supply and ground circuits of ESP® control module. If they are OK, go to «TROUBLESHOOTING FOR COMMUNICATION BUS OFF»(ref-585621-S26296018252013111200000) .
- Confirm that ignition mode of keyless push start system is in "OFF" and disconnect SUZUKI scan tool from DLC after completing check.
ESP® Control Module
As the data values are standard values estimated on the basis of values obtained from the normally operating vehicles by using a scan tool, use them as reference values. Even when the vehicle is in good condition, there may be cases where the checked value does not fall within each specified data range. Therefore, judgment as abnormal should not be made by checking with these data alone.
Note. Ignition mode stands for power supply mode according to engine switch operation in keyless push start system.
| Scan tool data | Vehicle condition | Condition/reference values |
|---|---|---|
| Battery Voltage | Ignition mode ON (Engine at stop) | 13.0 - 15.0 V |
| Pump Motor Driver | Inactive (Pump motor is not working) | 0.0 V |
| Active (Pump motor is working) | 13.0 - 15.0 V | |
| RF Wheel Speed | At stop (Vehicle is in stationary condition) | 0 km/h (0 mph) |
| LF Wheel Speed | At stop (Vehicle is in stationary condition) | 0 km/h (0 mph) |
| RR Wheel Speed | At stop (Vehicle is in stationary condition) | 0 km/h (0 mph) |
| LR Wheel Speed | At stop (Vehicle is in stationary condition) | 0 km/h (0 mph) |
| Brake Switch | Depressed brake pedal | ON |
| Released brake pedal | OFF | |
| Master Cyl Press | Depressed brake pedal | Over 0 ± 0.8 MPa |
| Released brake pedal | 0 ± 0.8 MPa | |
| G Sensor (Lateral) | Parking (Ignition mode ON, On the level) | 0 G |
| Right turning | 0.1 G | |
| Left turning | 0.1 G | |
| G sensor (In front and behind) | Parking (Ignition mode ON, On the level) | 0 G |
| Accelerating | 0.1 G | |
| Decelerating | 0.1 G | |
| Yaw Rate Sensor | Parking (Ignition mode ON, On the level) | 0 ± 4 deg/s |
| Right turning | 0 ± 4 deg/s or more | |
| Left turning | 0 ± 4 deg/s or less | |
| Steering Angle Sen | Front wheels are in straight-ahead position | 0 ± 3° |
| Rotate steering wheel once in clockwise | 360° ± 3° | |
| Rotate steering wheel once in counterclockwise | 360° ± 3° | |
| ESP® OFF SW State | ESP® OFF switch button is released | OFF |
| ESP® OFF switch button is pushed | ON | |
| Steering Angle Sig | Front wheels are in straight-ahead position (-5° to 5°) | Neutral |
| Other than above condition, or not calibrated | Not N | |
| Stability Control | Operating | ON |
| Not operating | OFF | |
| Hill Hold Control | Active brake is applied to vehicle on up slope | ON |
| Other than above condition | OFF | |
| TCSS Control (Brake) | Active brake is applied to wheel | ON |
| Other than above condition | OFF | |
| TCSS Control (Engine) | Engine torque control is operating | ON |
| Other than above condition | OFF |
SCAN TOOL DATA AND VEHICLE CONDITION CHART
ESP® Warning Light Does Not Come ON after Pressing Engine Switch to Change the Ignition Mode of Keyless Push Start System to "ON"
| Stability Control (ON, OFF) | This parameter informs whether active brake is operated or not when vehicle is over or understeering. |
|---|---|
| Hill Hold Control (ON, OFF) | This informs whether active brake is operated or not when vehicle is on upslope. |
| TCSS Control (Brake) (ON, OFF) | This informs whether active brake is operated or not when vehicle is accelerating. |
| TCSS Control (Engine) (ON, OFF) | This informs whether engine torque control is operated or not when vehicle is accelerating. |
PARAMETER INFORMATION REFERENCE
Scheme 52
Circuit Diagram
Refer to " CIRCUIT DIAGRAM " under ESP® WARNING LIGHT DOES NOT COME ON AFTER PRESSING ENGINE SWITCH TO CHANGE THE IGNITION MODE OF KEYLESS PUSH START SYSTEM TO "ON" .
Refer to " CIRCUIT DIAGRAM " under ESP® WARNING LIGHT DOES NOT COME ON AFTER PRESSING ENGINE SWITCH TO CHANGE THE IGNITION MODE OF KEYLESS PUSH START SYSTEM TO "ON" .
Refer to " CIRCUIT DIAGRAM " under ESP® WARNING LIGHT DOES NOT COME ON AFTER PRESSING ENGINE SWITCH TO CHANGE THE IGNITION MODE OF KEYLESS PUSH START SYSTEM TO "ON" .