Keyless Operation System
DTC C1912: Tire Inflation pressure Warning 1DTC C1922: Tire Inflation pressure Warning 2
DTC C1932: Tire Inflation pressure Warning 3
DTC C1942: Tire Inflation pressure Warning 4
CAUTION: If there is any problem in the CAN bus lines, an incorrect diagnostic trouble code may be set. Prior to this diagnosis, diagnose the CAN bus lines.
TPMS DTC SET CONDITION
When the tire pressure becomes lower than the specified value, the TPMS transmitter sends the signal to KOS-ECU, and then KOS-ECU sets this code.
TROUBLESHOOTING HINTS
The most likely causes for this DTC to set is:
- Drop of the tire pressure.
- Loose TPMS transmitter mounting nut.
- Flat tire.
- TPMS transmitter malfunction.
- KOS-ECU malfunction.
- CAN-bus line malfunction.
DIAGNOSIS
Required Special Tools:
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: Vehicle Communication Interface (V.C.I.)
- MB991827: M.U.T.-III USB Cable
- MB991910: M.U.T.-III Main Harness A
STEP 1. M.U.T.-III CAN bus diagnostics.
Use scan tool to diagnose the CAN bus lines.
Q: Is the check result normal?
YES : Go to Step 3.
NO : Repair the CAN bus lines. On completion, go to Step 2.
STEP 2. Diagnostic trouble code recheck after resetting CAN bus lines.
Q: Is DTC C1912, C1922, C1932 or C1942 set?
YES : Go to Step 3.
NO : The procedure is complete.
STEP 3. Tire pressure check
Check that the pressure of the tire corresponds to the set DTC is normal.
Q: Is the check result normal?
YES : Go to Step 5.
NO : Go to Step 4.
STEP 4. Tire check
Check that there is no abnormality for the items below.
- Flat tire
- Cracked tire
- Air leak from valve
- Loose TPMS transmitter mounting nut.
Q: Is the check result normal?
YES : Go to Step 5.
NO : Replace it. Then go to Step 7.
STEP 5. Tire pressure check by M.U.T.-III
1. Check the registered ID code by the transmitter ID check function.
2. Check the wheel to which the DTC is set by the transmitter check function.
3. Using the M.U.T.-III, check the relevant tire pressure.
4. Using the tire pressure gauge, check the tire pressure at the air valve of relevant tire. Then, measure the difference between that checked tire pressure and the tire pressure displayed at the procedure 3.
OK: 20 kPa or less
Q: Is the check result normal?
YES : Go to Step 6.
NO : Replace the TPMS transmitter and register the ID Codes.
STEP 6. Tire pressure check by M.U.T.-III
1. Check the registered ID codes by the transmitter ID Check function.
2. Check the wheel to which the DTC is set by the transmitter check function.
3. Using the M.U.T.-III, check the relevant tire pressure.
4. Using the tire pressure gauge, check the tire pressure at the air valve of relevant tire. Then, measure the difference between that checked tire pressure and the tire pressure displayed at the procedure 3.
OK: 20 kPa or less
Q: Is the check result normal?
YES : Go to Step 7.
NO : Replace the KOS-ECU and register the ID Codes. Then go to Step 7.
STEP 7. Recheck for diagnostic trouble code.
1. Correct the tire pressure for all wheels.
2. Turn the ignition switch to the "LOCK" (OFF) position.
3. Turn the ignition switch to the "ON" position.
4. Check if the DTC is set.
5. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the diagnostic trouble code C1912, C1922, C1932 or C1942 set?
YES : Start over at Step 1.
NO : The procedure is complete.