[ Model - ECLIPSE CROSS / Year - 2018 ]
2018 / ECLIPSE CROSS / EC - Workshop Manual
17 -ENGINE AND EMISSION CONTROL > CRUISE CONTROL > DIAGNOSIS CODE PROCEDURES > CODE NO. P0504: Brake lamp switch system
Code No. P0504: Malfunction of the Stop Lamp Switch System.
 
 

 
 
OPERATION
  • For the stop lamp switch, two switches, a stop lamp switch for the stop lamp illumination and a brake switch exclusively for the cruise control system, are incorporated to improve the reliability.
  • As for the stop lamp switch, when the brake pedal is depressed/released, the stop lamp switch ON/OFF signal is transmitted from the ETACS-ECU to the engine-ECU via CAN bus line.
  • As for the brake switch, the engine-ECU connector terminal BRK monitor the state of the brake switch. The brake switch turn ON/OFF when the brake pedal is depressed/released, and the input signal to the engine-ECU connector terminal BRK changes. According to this change, the engine-ECU judges the state of the brake switch.
 
 
DIAGNOSIS CODE SET CONDITIONS
Check Condition
  • The cruise control display screen is displayed.
Judgement Criteria
  • Open/short in stop lamp switch circuit.
  • Open circuit in the brake switch circuit (between engine-ECU connector terminal BRK and earth).
  • Malfunction of CAN bus line.
 
 
PROBABLE CAUSES
  • Malfunction of CAN bus system.
  • Damaged harness or connector.
  • Malfunction of the fuse No.14.
  • Malfunction of the stop lamp switch.
  • Malfunction of the ETACS-ECU.
  • Malfunction of the engine-ECU.
 
 
DIAGNOSIS PROCEDURE
caution
  • If there is any problem in the CAN bus lines, an incorrect diagnosis code may be set. Prior to this diagnosis, diagnose the CAN bus lines.
  • Before replacing the ECU, ensure that the CAN bus lines is normal.
STEP 1. M.U.T.-IIISE CAN bus diagnostics.
Use M.U.T.-IIISE to perform the CAN bus diagnosis.
Is the check result normal?
Go to Step 2.
Repair the CAN bus lines (Refer to GROUP 54C - Troubleshooting, CAN Bus Diagnostics Table ).
 
STEP 2. M.U.T.-IIISE data list.
Check the following data list (Refer to ).
  • Item No.74: Stop lamp switch
Is the check result normal?
Go to Step 6.
Go to Step 3.
 
STEP 3. Check the stop lamp operation.
Check the stop lamp operation.
OK:
  • Brake pedal depressed: Stop lamp will illuminate
  • Brake pedal not depressed: Stop lamp does not illuminate
Is the check result normal?
Go to Step 4.
Check the stop lamp system (Refer to GROUP 54A - Rear Combination Lamp, Symptom Procedures, The stop lamps do not illuminate or go out normally ).
 
STEP 4. Check the ETACS system data list.
Using M.U.T.-IIISE, check the ETACS system data list (Refer to GROUP 54A - ETACS, Troubleshooting, data list reference table ).
  • Item No.113: Stop lamp switch
Is the check result normal?
Go to Step 5.
Replace the ETACS-ECU (Refer to GROUP 54A - ETACS, ETACS-ECU ).
 
STEP 5. M.U.T.-IIISE data list.
Check the following data list (Refer to ).
  • Item No.74: Stop lamp switch
Is the check result normal?
It can be assumed that this malfunction is intermittent (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points, How to Cope with Intermittent Malfunction ).
Replace the engine-ECU (Refer to GROUP 13A - Engine-ECU ).
 
STEP 6. M.U.T.-IIISE data list.
Check the following data list (Refer to ).
  • Item No.89: Brake switch
Is the check result normal?
Go to Step 11.
Go to Step 7.
 
STEP 7. Check of open circuit, short circuit, and damage in BRK line between engine-ECU connector and stop lamp switch connector.
Is the check result normal?
Go to Step 8.
Repair the connector(s) or wiring harness.
 
STEP 8. Check of open circuit, and damage in earth line between stop lamp switch connector and body earth.
Is the check result normal?
Go to Step 9.
Repair the connector(s) or wiring harness.
 
STEP 9. Check the stop lamp switch.
Refer to GROUP 35A - Brake Pedal, Inspection, Stop Lamp Switch Check .
Is the check result normal?
Go to Step 10.
Replace the stop lamp switch (Refer to GROUP 35A - Brake Pedal ).
 
STEP 10. M.U.T.-IIISE data list.
Check the following data list (Refer to ).
  • Item No.89: Brake switch
Is the check result normal?
It can be assumed that this malfunction is intermittent (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points, How to Cope with Intermittent Malfunction ).
Replace the engine-ECU (Refer to GROUP 13A - Engine-ECU ).
 
STEP 11. Read the diagnosis code.
(1) Use the M.U.T.-IIISE, erase the diagnosis code of the cruise control system.
(2) Turn the ignition switch to the "ON" position, and press the cruise control ON/OFF switch to turn the cruise control system to ON (the cruise control display screen is turned on).
(3) With the cruise control switches not operated, depress the brake pedal for several seconds, and then read the diagnosis code of the cruise control system (Refer to ).
Is diagnosis code No. P0504 set?
Replace the engine-ECU (Refer to GROUP 13A - Engine-ECU ).
It can be assumed that this malfunction is intermittent (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points, How to Cope with Intermittent Malfunction ).