U1114
U1114-LOST COMMUNICATION WITH LEFT FRONT TIRE PRESSURE TRIGGER MODULE
For a complete wiring diagram, refer to the Wiring Information. Electrical Diagrams
Theory of Operation
The Tire Pressure Monitoring (TPM) Transponder is used to automatically learn the location of each wheel TPM Sensor on the vehicle. The module is controlled and activated in sequence by the Wireless Ignition Node (WIN) over a LIN bus. When activated, the module will generate a 125 KHz signal of sufficient field strength to trigger the TPM Transponder and force a low frequency RF transmission from the TPM Sensor.
- When Monitored:
Continuously with the ignition on and Ignition Off Draw (IOD) fuse installed.
- Set Condition:
If the Wireless Ignition Node (WIN) fails to receive bus messages from the Tire Pressure Monitoring (TPM) Transponder for Two consecutive counts of TPM Transponder not responding to a communication check.
1. VERIFY DTC IS ACTIVE
NOTE: Make sure the IOD fuse is installed and battery voltage is between 10 and 16 volts before proceeding.
1. Ignition on, engine not running.
2. With the scan tool, read and record DTCs.
3. With the scan tool, erase DTCs.
4. Cycle the ignition switch.
5. With the scan tool, read DTCs.
Does this DTC reset?
Yes
- Go To 2
No
- Perform the Stored Lost Communication test procedure. Stored Lost Communication DTCs.
- Perform the BODY VERIFICATION TEST. Body Verification Test.
2. (F943) FUSED IGNITION SWITCH OUTPUT (RUN) CIRCUIT OPEN OR HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the Tire Pressure Transponder harness connector.
3. Ignition on, engine not running.
4. Using a 12-volt test light connected to ground, check the (F943) Fused Ignition Switch Output (Run) circuit.
NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.
Does the test light illuminate and brightly?
Yes
- Go To 3
No
- Repair the (F943) Fused Ignition Switch Output (Run) circuit for an open circuit or high resistance.
- Perform TPM VERIFICATION TEST Tire Pressure Monitor (TPM) Verification Test.
3. (Z904) GROUND CIRCUIT(S) OPEN OR HIGH RESISTANCE
1. Using a 12-volt test light connected to 12 volts, check each of the (Z904) Ground circuit(s).
NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.
Does the test light illuminate and brightly?
Yes
- Go To 4
No
- Repair the (Z904) Ground circuit(s) for an open circuit or high resistance.
- Perform TPM VERIFICATION TEST Tire Pressure Monitor (TPM) Verification Test.
4. (D508) COM - LIN TIRE PRESSURE MONITOR LAN CIRCUIT SHORT TO VOLTAGE
1. Turn the ignition off.
2. Disconnect the Wireless Ignition Node (WIN) harness connector.
3. Ignition on, engine not running.
4. Measure the voltage of the (D508) COM - LIN Tire Pressure Monitor LAN circuit.
Is there any voltage present?
Yes
- Repair the (D508) COM - LIN Tire Pressure Monitor LAN circuit for a short to voltage.
- Perform TPM VERIFICATION TEST Tire Pressure Monitor (TPM) Verification Test.
No
- Go To 5
5. (D508) COM - LIN TIRE PRESSURE MONITOR LAN CIRCUIT SHORT TO GROUND
1. Turn the ignition off.
2. Measure the resistance between ground and the (D508) COM - LIN Tire Pressure Monitor LAN circuit.
Is the resistance below 5.0 Ohms?
Yes
- Repair the (D508) COM - LIN Tire Pressure Monitor LAN circuit for a short to ground.
- Perform TPM VERIFICATION TEST Tire Pressure Monitor (TPM) Verification Test.
No
- Go To 6
6. (D508) COM - LIN TIRE PRESSURE MONITOR LAN CIRCUIT OPEN OR HIGH RESISTANCE
1. Use a jumper wire with one end connected to ground and the other to the (D508) COM - LIN Tire Pressure Monitor LAN circuit in the Left Front Tire Pressure Transponder harness connector.
2. Using a 12-volt test light connected to battery voltage, probe the (D508) COM - LIN Tire Pressure Monitor LAN circuit in the WIN harness connector.
NOTE: The test light should be illuminated and bright. Compared the brightness to that of a direct connection to the battery.
Does the test light illuminate brightly?
Yes
- Go To 7
No
- Repair the (D508) COM - LIN Tire Pressure Monitor LAN circuit for an open circuit or high resistance.
- Perform TPM VERIFICATION TEST Tire Pressure Monitor (TPM) Verification Test.
7. (D508) COM-LIN TIRE PRESSURE MONITOR LAN CIRCUIT OPEN
1. Turn the ignition off.
2. With an ohmmeter measure the resistance of the (D508) COM-LIN Tire Pressure Monitor LAN circuit.
Is the resistance below 5 Ohms?
Yes
- Go To 8
No
- Repair or replace the open circuit.
- Perform TPM VERIFICATION TEST Tire Pressure Monitor (TPM) Verification Test.
8. POWER AND GROUND CIRCUIT OPEN
1. Ignition on, engine not running.
2. With a voltmeter measure the voltage between the power and ground circuit at the TPM Transponder.
Is the voltage at least the same as battery voltage?
Yes
- Go To 9
No
- Repair the open circuit.
- Perform TPM VERIFICATION TEST Tire Pressure Monitor (TPM) Verification Test.
9. CHECK FOR ADDITIONAL TPM TRANSPONDER COMMUNICATION RELATED DTCs
1. With the scan tool, select Network View and select Advanced.
Is there more than one module with active DTCs Logged Against the WIN?
Yes
- Replace the Wireless Ignition Node (WIN).
- Perform TPM VERIFICATION TEST Tire Pressure Monitor (TPM) Verification Test.
No
- Replace the Tire Pressure Monitoring (TPM) Transponder.
- Perform TPM VERIFICATION TEST Tire Pressure Monitor (TPM) Verification Test.