C1342

C1342

Component Location:

General Description
The LFI (Low Frequency Initiator) is located at each vehicle wheel house (FL, FR, RL, RR). High Line systems are fitted with LFI units. An LFI unit mounted in each wheel well to enable the receiver unit to determine the vehicle position of each sensor for which it has a stored ID code. Using a digital bi-directional serial control line to each LFI, the receiver can activate an LFI to send out an LF message and trigger the sensor near its location to respond with an RF transmission. By activating LFI units one at a time, the receiver can automatically locate the vehicle position of each sensor. For fault detection, the LFI will report back its "operating properly" status to the receiver via the control line. The LF communication prolong battery life (through state changes) and determine sensor location (through one-to-one handshaking between LFI and transmitter).

DTC Description
This DTC indicates that the receiver has been unable to initiate front left sensor with a particular initiator during Auto-Location.

DTC Detecting Condition:

Schematic Diagram:

Monitor Scantool Data
1. Connect 'TPMS exciter' or scantool to Data Link Connector (DLC).
2. Select "TPMS DIAGNOSIS" mode.
3. Select the "FULL" mode of "CURRENT DATA" function.
4. Monitor the parameter of front left sensor on the 'TPMS exciter' or scantool after 13 minutes.









5. Is parameter normal?

YES
- Fault is intermittent. It has been repaired and TPMS receiver module memory is not cleared yet.
- Go to "Verification of vehicle Repair" procedure.

NO - Go to "W/Harness Inspection" procedure.

Terminal and Connector Inspection
1. Many malfunctions in the electrical system are caused by poor harness and terminal condition. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
2. Thoroughly check all connectors (and connections) for looseness, bending, corrosion, contamination, deterioration, and/or damage.
3. Has a problem been found?

YES - Repair if necessary and then go to "Verification of Vehicle Repair" procedure.

NO - Go to "Power Circuit Inspection" procedure.

Power Supply Circuit Inspection
1. Engine "OFF".
2. Connect TPMS receiver connector.
3. Engine "ON".
4. Measure waveform between terminal "5" of TPMS receiver harness connector and chassis ground by using a oscilloscope.






5. Is the measured waveform within specifications?

YES - Go to "Return Circuit Inspection" procedure.

NO
- Check for supply harness.
- Repair if necessary and then go to "Verification of Vehicle Repair" procedure.

Return Circuit Inspection
1. Engine "OFF".
2. Connect TPMS receiver connector.
3. Engine "ON".
4. Measure voltage between terminal "3" of TPMS receiver harness connector and chassis ground.

Specification : 0 V






5. Is the measured voltage within specifications?

YES - Go to "Request Circuit Signal Inspection" procedure.

NO
- Check for return harness.
- Repair if necessary and then go to "Verification of Vehicle Repair" procedure.

Request Signal Circuit Inspection
6. Engine "OFF".
7. Disconnect TPMS receiver connector and Initiator connector.
8. Measure resistance between terminal "2" of TPMS receiver harness connector and terminal "10" of Initiator harness connector.

Specification : Infinite ohms






9. Is the measured resistance within specifications?

YES - Go to "Component Inspection" procedure.

NO
- Check for request signal harness.
- Repair if necessary and then go to "Verification of Vehicle Repair" procedure.

Component Inspection
1. Turn ON 'TPMS exciter'.
2. Select "TIRE SNSR CONFIG (EXCITER)" mode.
3. Execute "SET SENSOR STATUS" of front right sensor.






4. Is data unable to be retrieved for front right sensor?

YES
- Replace front left TPMS sensor and register sensor ID with 'TPMS exciter'.
- Go to "Verification of Vehicle Repair" procedure.

NO
- Substitute with a known-good Initiator and check for proper operation.
- If the problem is corrected, replace Initiator and then go to "Verification of Vehicle Repair" procedure.
- If the problem is not corrected, substitute with a known-good TPMS receiver module and check for proper operation.
- If the problem is corrected, replace TPMS receiver module and then go to "Verification of Vehicle Repair" procedure.

Verification of Vehicle Repair
After a repair, it is essential to verify that the fault has been corrected.
1. Connect TPMS exciter or scantool and select "Diagnostic Trouble Codes (DTCs)" mode
2. Using a TPMS exciter or scantool, Clear DTC.
3. Operate the vehicle within DTC Enable conditions in General information.
4. Are any DTCs present?

YES - Go to the applicable troubleshooting procedure.

NO - System performing to specification at this time.