The brake pedal stroke sensor is supplied with the
5-V power from the EV-ECU, converts the brake pedal opening angle into the voltage, and outputs
it to the EV-ECU.
DIAGNOSIS CODE SET CONDITIONS
When not depressing a brake pedal, the brake pedal stroke sensor
output voltage is below the specified value, or when the stop lamp switch is ON, the brake fluid
pressure is beyond specified value, the brake pedal stroke sensor output voltage is below the
specified value, diagnosis code No. P1B37 will be set.
If the brake pedal stroke sensor output voltage is outside the range of 1.5 V to
3.8 V when the stop lamp switch is OFF, the diagnosis code No. P1B37 will be set.
PROBABLE CAUSES
Incorrect brake pedal height when the brake pedal is
not depressed
Brake pedal stroke sensor malfunction
DIAGNOSTIC PROCEDURE
STEP 1. Brake pedal check
Refer to GROUP 35A - On-vehicle Service/Brake Pedal Check and Adjustment
Q.
Is the check result normal?
Go to Step 2
Brake pedal height check (Refer to GROUP 35A - On-vehicle Service/Brake
Pedal Check and Adjustment ).
STEP 2. M.U.T.-III data list
Check the following data list (Refer to ).
Item 85: Brake pedal stroke sensor voltage
Item 87: Brake sensor stroke value
Item 190: Brake pedal stroke sensor installation
Q.
Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/How
to Cope with Intermittent Malfunctions ).
Go to Step 3.
STEP 3. Check whether the diagnosis code is reset
Recheck if the diagnosis code is set .
(1)Erase the diagnosis code.
(2)Turn the electric motor switch from "LOCK" (OFF) position to "ON" position.
(3)The brake pedal is depressed for seneral times.
(4)Check if the diagnosis code is set.
Q.
Is the diagnosis code set?
Replace the brake pedal assembly (Refer to GROUP 35A - Brake Pedal <LHD>, <RHD>).
Then go to Step 4.
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/How
to Cope with Intermittent Malfunctions ).
STEP 4. Check whether the diagnosis code is reset
Recheck if the diagnosis code is set .
(1)Erase the diagnosis code.
(2)Turn the electric motor switch from "LOCK" (OFF) position to "ON" position.
(3)The brake pedal is depressed for seneral times.
(4)Check if the diagnosis code is set.
Q.
Is the diagnosis code set?
Replace the EV-ECU (Refer to ). Then go to Step
5.
The diagnosis is complete.
STEP 5. Check whether the diagnosis code is reset
Recheck if the diagnosis code is set .
(1)Erase the diagnosis code.
(2)Turn the electric motor switch from "LOCK" (OFF) position to "ON" position.
(3)The brake pedal is depressed for seneral times.
Go to Step 2
Brake pedal height check (Refer to GROUP 35A - On-vehicle Service/Brake
Pedal Check and Adjustment 