Code No. C1912: Tyre air pressure low, Tyre1
Code No. C1922: Tyre air pressure low, Tyre2
Code No. C1932: Tyre air pressure low, Tyre3
Code No. C1942: Tyre air pressure low, Tyre4
Code No. C1952: Tyre air pressure low, Tyre5


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 - CAN Bus Diagnostics Table ).

DIAGNOSTIC FUNCTION


When the tyre pressure included in the signal from the TPMS transmitter is less than the specified value, KOS&OSS-ECU sets these codes.

PROBABLE CAUSES


The most likely causes for this diagnosis code to be set are:

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnosis.
Use the 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 - CAN Bus Diagnostics Table ). On completion, go to Step 2.

STEP 2. Diagnosis code recheck after resetting CAN bus lines.
Recheck if diagnosis code Nos. C1912, C1922, C1932, C1942 or C1952 is set.
(1)Turn the ignition switch from the "LOCK" (OFF) to "ON" position.
(2)Check if the diagnosis code is set.
(3)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is diagnosis code Nos. C1912, C1922, C1932, C1942 or C1952 set?
Go to Step 3.
The procedure is complete.

STEP 3. Tyre check.
Check that there is no abnormality for the items below.

  • Flat tyre
  • Cracked tyre
  • Air leak from valve

Q. Is the check result normal?
Go to Step 4.
Replace or repair it. Then go to Step 4.

STEP 4. Check whether the diagnosis code is set again.
Recheck if the diagnosis code is set.
(1)Turn the ignition switch to the "LOCK" (OFF) to "ON" position, and adjust the pressure to the recommended tyre pressure.
(2)Check if the diagnosis code is set.

Q. Is diagnosis code Nos. C1912, C1922, C1932, C1942 or C1952 set?
Go to Step 5.
The procedure is complete.

STEP 5. Check whether the diagnosis code is set again.
Recheck if the diagnosis code is set.
(1)Drive the vehicle for 5 minutes.
note Even within 5 minutes, if the TPMS warning lamp goes out, finish the driving and perform the operation (2).
(2)Check if the diagnosis code is set.

Q. Is diagnosis code Nos. C1912, C1922, C1932, C1942 or C1952 set?
Go to Step 6.
The procedure is complete.

STEP 6. Tyre pressure check by M.U.T.-III.
(1)Perform the transmitter check using the M.U.T.-III (Refer to ), and check the tyre pressure values of all the wheels.
(2)Check the tyre pressure of all the wheels using the tyre pressure gauge.
(3)Compare the measured value (1) with (2).
OK: 20 kPa or less
note The TPMS transmitter which cannot be checked may be faulty or the ID code may not be registered, thus do not replace it, but register the ID code. If the transmitter is faulty, it is replaced in the ID code registration process.

Q. Is the check result normal?
Replace the KOS&OSS-ECU (Refer to GROUP 42B - KOS&OSS-ECU). Then go to Step 8.
Replace the TPMS transmitter (Refer to ), and register the ID codes (Refer to ). Then go to Step 7.

STEP 7. Check whether the diagnosis code is set again.
Recheck if the diagnosis code is set.
(1)Turn the ignition switch from the "LOCK" (OFF) to "ON" position.
(2)Check if the diagnosis code is set.
(3)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is diagnosis code Nos. C1912, C1922, C1932, C1942 or C1952 set?
Replace the KOS&OSS-ECU (Refer to GROUP 42B - KOS&OSS-ECU) and register the ID codes (Refer to ). Then go to Step 8.
The procedure is complete.

STEP 8. Check whether the diagnosis code is set again.
Recheck if the diagnosis code is set.
(1)Turn the ignition switch from the "LOCK" (OFF) to "ON" position.
(2)Check if the diagnosis code is set.
(3)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is diagnosis code Nos. C1912, C1922, C1932, C1942 or C1952 set?
Start over at Step 1.
The procedure is complete.