2007 Liberty KJ Factory Service Manual 22 - TIRES/WHEELS

RIGHT FRONT TIRE PRESSURE TRIGGER MODULE PERFORMANCE





For a complete wiring diagram Refer to Section 8W

Theory of Operation


The Tire Pressure Trigger Module, also known as a transponder, is used to automatically learn the location of each wheel sensor on the vehicle. The module is controlled and activated in sequence by the Wireless Control Module (SKREEM) over a LIN bus. When activated, the module will generate a 125 KHz signal of sufficient field strength to trigger the tire pressure sensor and force a RF transmission from the sensor.



Possible Causes
 
INTERMITTENT TIRE PRESSURE TRIGGER MODULE PERFORMANCE DTC
 
(D508) COM - LIN TIRE PRESSURE MONITOR LAN CIRCUIT SHORT TO VOLTAGE
 
(D508) COM - LIN TIRE PRESSURE MONITOR LAN CIRCUIT SHORT TO GROUND
 
(D508) COM - LIN TIRE PRESSURE MONITOR LAN CIRCUIT OPEN OR HIGH RESISTANCE
 
(F22) FUSED IGNITION SWITCH OUTPUT (RUN) CIRCUIT OPEN OR HIGH RESISTANCE
 
(Z384) GROUND CIRCUIT(S) OPEN OR HIGH RESISTANCE
 
TIRE PRESSURE TRIGGER MODULE
 
WIRELESS CONTROL MODULE (SKREEM)
 




Diagnostic Test

1. DTC STATUS IS ACTIVE

Turn the ignition on.
With the scan tool, select View DTCs in the Wireless Control Module (SKREEM).

Is the DTC status Active at this time?

Yes


No

2. (F22) FUSED IGNITION SWITCH OUTPUT (RUN) CIRCUIT OPEN OR HIGH RESISTANCE



Turn the ignition on.
Using a 12–volt test light connect to ground, check the (F22) 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.



Is the test light illuminated and bright?

Yes


No

3. (Z384) GROUND CIRCUIT(S) OPEN OR HIGH RESISTANCE



Using a 12–volt test light connect to 12 volts, check each of the (Z384) Ground circuit(s).

NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.



Is the test light illuminated and bright?

Yes


No

4. (D508) COM - LIN TIRE PRESSURE MONITOR LAN CIRCUIT SHORT TO VOLTAGE



Turn the ignition off.
Disconnect the Tire Pressure Transponder harness connector.
Disconnect the Sentry Key Remote Entry Module harness connector.
Turn the ignition on.
Measure the voltage of the (D508) COM - LIN Tire Pressure Monitor LAN circuit.

Is there any voltage present?

Yes


No

5. (D508) COM - LIN TIRE PRESSURE MONITOR LAN CIRCUIT SHORT TO GROUND



Turn the ignition off.
Measure the resistance between ground and the (D508) COM - LIN Tire Pressure Monitor LAN circuit.

Is the resistance below 5.0 ohms?

Yes


No

6. (D508) COM - LIN TIRE PRESSURE MONITOR LAN CIRCUIT OPEN OR HIGH RESISTANCE

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 Front Left Pressure Tire Transponder harness connector.
Using a 12-Volt test light connected to battery voltage, probe the (D508) COM - LIN Tire Pressure Monitor LAN circuit in the SKREEM 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 bright?

Yes


No

7. TIRE PRESSURE TRIGGER MODULE

Turn the ignition off.
Replace the appropriate Tire Pressure Trigger Module in accordance with the Service Information.
With the scan tool, clear DTCs in the Wireless Control Module (SKREEM).
Test Drive the vehicle for a minimum of 10 minutes with vehicle speed greater than 15 m.p.h.
With the scan tool, select View DTCs in the Wireless Control Module (SKREEM).

Does the DTC reset or is the status Active for this DTC?

Yes


No

8. WIRELESS CONTROL MODULE (SKREEM)

View repair.



Repair

9. INTERMITTENT TIRE PRESSURE TRIGGER MODULE DTC

The conditions necessary to set this DTC are not present at this time.
Using the wiring schematic as a guide, inspect the wiring and connectors relative to this circuit.
Refer to any Technical Service Bulletins that may apply to this condition.
With the scan tool, clear DTCs in the Wireless Control Module (SKREEM).
Test Drive the vehicle for a minimum of 10 minutes with vehicle speed greater than 15 m.p.h.
With the scan tool, select View DTCs in the Wireless Control Module (SKREEM).

Does the DTC reset or is the status Active for this DTC?

Yes
  • Return to the first step of this test and perform the diagnostic procedure.


No
  • Test complete.