No.1 ESS (EMERGENCY STOP SIGNAL SYSTEM) DOES NOT OPERATE [EMERGENCY STOP SIGNAL SYSTEM (ESS)]

id0903j7004200

1 | ESS (Emergency Stop Signal system) does not operate
DESCRIPTION | • Hazard warning lights do not flash even though vehicle decelerates suddenly. • Hazard warning lights end flashing before vehicle stops (emergency stop hazard warning mode, vehicle speed at approx. 10 km/h {6.2 mph}) while system operates.
POSSIBLE CAUSE | Hazard warning light flash malfunction • BCM malfunction (flashing hazard warning light circuit malfunction) DSC/RSC CM do not recognize vehicle speed. • Malfunction in ABS wheel speed sensor related parts ― ABS wheel-speed sensor malfunction ― ABS wheel-speed sensor rotor malfunction • DSC/RSC CM malfunction BCM does not recognize sudden deceleration hazard warning mode request signal. • DSC/RSC CM malfunction (signal is not output) • BCM malfunction • Communication error between DSC/RSC CM and BCM BCM does not recognize emergency stop hazard warning mode request signal. • Brake switch signal malfunction ― Brake switch malfunction ― Open or short circuit between brake switch and PCM terminal 1S • Vehicle speed signal malfunction ― Communication error between PCM and DSC/RSC CM • BCM malfunction Road condition may be affected. (emergency braking warning system is normal) • Grip level of tires is low ― Driving on a low-traction surface ― Tire wear (hydroplaning)

Diagnostic Procedure

Step | Inspection | Action
--- | --- | ---
1 | VERIFY DTCs • Retrieve DTCs for the PCM, DSC/RSC CM, and BCM. (See ON-BOARD DIAGNOSTIC TEST [MZI-3.7].) (See ON-BOARD DIAGNOSIS [DSC/RSC].) (See DTC INSPECTION [BCM].) • Are any DTCs output? | Yes | Go to the applicable DTC inspection. (See DTC TABLE [MZI-3.7].) (See ON-BOARD DIAGNOSIS [DSC/RSC].) (See DTC TABLE [BCM].)
No | Go to the next step.
2 | VERIFY MALFUNCTION CONDITION • Do the hazard warning lights flash in the emergency stop hazard warning mode while the vehicle speed is 10 km/h {6.2 mph} or less? | Yes | Go to the next step.
No | Go to Step 5.
3 | DETERMINE IF MALFUNCTION CAUSED BY PCM INPUT SIGNAL ERROR • Monitor the PCM PID “BOO” using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST [MZI-3.7].) • Are the monitoring values normal? | Yes | May be affected by driving conditions (emergency braking warning system is normal). If a malfunction occurs, replace the BCM. (See BODY CONTROL MODULE (BCM) REMOVAL/INSTALLATION.)
No | Go to the next step.
4* | INSPECT BRAKE SWITCH SIGNAL FOR MALFUNCTION CAUSED BY OPEN OR SHORT CIRCUIT • Inspect the wiring harness between the brake switch and PCM 1S for an open or short circuit. • Is there any open or short circuit? | Yes | Repair the malfunctioning part for an open or short circuit.
No | Replace the brake switch. (See BRAKE PEDAL REMOVAL/INSTALLATION [L.H.D.].)
5 | INSPECT FLASHING HAZARD WARNING LIGHT CIRCUIT FOR MALFUNCTION • Flashes the hazard warning lights using the hazard warning switch. • Do the hazard warning lights flash? | Yes | Go to the next step.
No | Replace the BCM. (See BODY CONTROL MODULE (BCM) REMOVAL/INSTALLATION.)
6 | DETERMINE IF MALFUNCTION CAUSED BY ABS OPERATION MALFUNCTION • Inspect the ABS operation at 10—20 km/h {6.2—12.0 mph}. • Is the ABS operation normal? | Yes | System may be affected by road conditions (emergency braking warning system is normal). If the malfunction recurs, replace the BCM. (See BODY CONTROL MODULE (BCM) REMOVAL/INSTALLATION.)
No | • Inspect the tires for the following: ― Tire air pressure (are all four tires at recommended pressure?) ― Tire wear condition (is tire wear uniform on all four tires, or is it different?) ― Tire size Adjust the malfunctioning tire or replace it.