No.2 ESS (EMERGENCY STOP SIGNAL SYSTEM) OPERATES WHILE NOT UNDER OPERATION CONDITIONS [EMERGENCY STOP SIGNAL SYSTEM (ESS)]

id0903j7004400

2 | ESS (Emergency Stop Signal system) operates while not under operation conditions
DESCRIPTION | • Hazard warning lights flash while driving • Hazard warning lights flash even though deceleration is done without decelerating rapidly.
POSSIBLE CAUSE | Hazard warning light flash malfunction • Hazard warning switch malfunction (temporary short circuit caused by vibration while vehicle is driven) ― Hazard warning switch malfunction ― Short circuit to ground in wiring harness between hazard warning switch and BCM terminal 5M • BCM malfunction (hazard warning light flash circuit disabled) BCM does not recognize sudden deceleration hazard warning mode request signal • DSC/RSC CM malfunction (false signal is output) • BCM malfunction • Communication error between DSC/RSC CM and BCM Sudden deceleration wheel speed is detected • 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* | DETERMINE IF MALFUNCTION CAUSED BY HAZARD WARNING SWITCH SIGNAL ERROR • Monitor the BCM PIDs “HAZARD” using the M-MDS: (See PID/DATA MONITOR INSPECTION [BCM].) • Are the monitoring values normal? | Yes | Go to Step 4.
No | Go to the next step.
3 | INSPECT HAZARD WARNING SWITCH FOR MALFUNCTION • Inspect the hazard warning switch. (See HAZARD WARNING SWITCH INSPECTION.) • Is the hazard warning switch normal? | Yes | Repair for a short to ground in the wiring harness between the hazard warning switch and BCM terminal 5M.
No | Replace the hazard warning switch. (See HAZARD WARNING SWITCH REMOVAL/INSTALLATION.)
4 | INSPECT TIRES FOR MALFUNCTION • 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 • Are the tires 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 | Adjust the malfunctioning tire or replace the tire.