Code No. C1000
Abnormality in stop lamp switch circuit
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 (Refer to GROUP
54C, Trouble code diagnosis ).
OPERATION
ETACS-ECU sends the ON signal generated when the brake pedal is depressed and OFF signal
generated when it is released to ASC-ECU via the CAN bus lines.
DIAGNOSIS CODE SET CONDITIONS
This diagnosis code is set in the following case.
When the vehicle has run for a long time with the stop lamp switch turned
ON.
When the OFF status of the stop lamp switch does not match the vehicle attitude
PROBABLE CAUSES
Improper adjustment of stop lamp switch installation position
Stop lamp switch malfunction
Malfunction of the stop lamp switch
Damaged wiring harness and connectors
Malfunction of ETACS-ECU
ASC-ECU malfunction
DIAGNOSIS PROCEDURE
STEP 1. M.U.T.-III CAN bus diagnosis
Use M.U.T.-III to diagnose the CAN bus lines.
Q.
Is the check result normal?
Go to Step 3.
Repair the CAN bus lines (Refer to GROUP 54C - Troubleshooting ).
On completion, go to Step 2.
STEP 2. Diagnosis code recheck after resetting CAN bus lines
Q.
Is the diagnosis code No. C1000 set?
Go to Step 3.
This diagnosis is complete.
STEP 3. Stop lamp operation check
(1)Turn the ignition switch to the ON position.
(2)Check the stop lamp operation when the brake pedal is depressed. Check that the
stop lamp illuminates when the brake pedal is depressed and that it goes out when the brake
pedal is released. OK:
When the brake pedal is released: OFF When the brake pedal is depressed: ON
Q.
Is the check result normal?
Go to Step 10.
Go to Step 4.
STEP 4. Check for stop lamp switch installation
Refer to GROUP 35A - On-vehicle Service .
Q.
Is the check result normal?
Go to Step 5.
Install the stop lamp switch correctly.
STEP 5. Stop lamp switch continuity check
(1)Remove the stop lamp switch (Refer to GROUP 35A -Brake Pedal ).
(2)Connect the circuit tester (Ω range) to the stop lamp switch connector terminals
No. 1 and 2. (3)When no continuity is detected with the plunger pressed from the edge of the outer
case by the dimension shown in the figure and when continuity is detected with the plunger released,
the stop lamp switch is in good condition.
Q.
Is the check result normal?
Go to Step 6.
Replace the stop lamp switch.
STEP 6. Voltage measurement at C-304 ETACS-ECU connector
(1)Turn the ignition switch to the ON position.
(2)Measure the voltage between the terminal No. 1 and the body earth. OK: Approximately battery voltage
The short circuit between the C-304 ETACS-ECU connector terminal No. 1 and the
C-109 stop lamp switch connector terminal No. 2 may be present. Repair the wiring harness between
the C-304ETACS-ECU connector terminal No. 1 and the C-109 stop lamp switch connector terminal
No. 2.
The short circuit between the C-131 intermediate connector terminal No. 9 and
the C-126 stop lamp switch connector terminal No. 1. may be present. Repair the wiring harness
between the C-131 intermediate connector terminal No. 9 and the C-126 stop lamp switch connector
terminal No. 1.
Repair the defective connector.
STEP 10. Voltage measurement at C-312 ETACS-ECU connector
(1)Turn the ignition switch to the ON position.
(2)Measure the voltage between the terminal No. 16 and the body earth. OK: Approximately 5 V
The short circuit between the C-312 ETACS-ECU connector terminal No. 16 and the
C-126 stop lamp switch connector terminal No. 1 may be present. Repair the wiring harness between
the C-312 ETACS-ECU connector terminal No. 16 and the C-126 stop lamp switch connector terminal
No. 1.
Repair the defective connector.
STEP 12. Check whether the diagnosis code is reset.